Inquiry Science
How does this affect the magnetic field around the wires?
NOT A. The field gets stronger.
Which imaging technique uses radiation that is emitted from the material being imaged?
NOT A. X-ray radiography
Which shows the order of mechanical advantage from least to greatest?
NOT A. Y, X, W, Z
Where do the three rays in a ray diagram start?
NOT C. at a focal point on the same side of the lens
Which demonstrates conduction?
NOT D. a bulb releasing light energy
Which is a use of fiber optics?
NOT D. writing and reading CDs and DVDs
When light bends around an object, the light is ____.
REFRACTED
Rahul sits in a chair reading a book. Which force is equal to the force Rahul exerts on Earth?
Rahul's weight
Inertia
Resist changes in the state of motion
Which portrays inadequate data?
Rupal determines aluminum is the most reactive metal by completing only half of her experiment.
Jenny is studying a compound that has two oxygen atoms and one nitrogen atom. Which statement describes the subscripts she will use to write the chemical formula?
She will use one 2 as a subscript.
A cannonball is launched from a cannon. The CHANGE IN VELOCITY on the cannon compared to the cannonball is
Smaller than on the cannonball
The substance that gets broken down in a homogeneous mixture is the ___.
Solute
Screening.
Sometimes, though, it is not practical or safe to use your fingers (or a fork or tweezers) to separate the pieces of a mixture. In such cases, a process called screening could be used to separate different pieces of the mixture based on their particle size. In the screening process, a series of different screens are used to sift smaller particles out of the overall mixture.
As Chelsea removes her clothes from the dryer, she sees sparks, which are examples of ____.
Static discharge
When hydrogen peroxide bubbles, it is undergoing a chemical change. Which statement best describes what is happening?
The atoms in hydrogen peroxide are breaking apart and forming new types of molecules.
What is a limitation of using a chemical formula, such as C6H12O6, to represent a compound?
The chemical formula does not show how the atoms are connected to one another.
Density involves the amount of a material in a certain volume. When a material changes phases, it changes in density in a predictable way as the amount of material stays the same but the molecules get farther apart or closer together. Water has solid and liquid states that do not follow these predictions of density in the phases of matter.
The liquid state is more dense than the solid state.
Which describes an object's speed in free fall?
The object falls faster and faster until it strikes the ground.
Which statement best compares the accelerations of two objects in free fall?
The objects have the same acceleration.
Why can a hydrogen atom form a covalent bond without fulfilling the octet rule?
The octet rule only applies to bonds formed by trading electrons.
A student is asked to describe the path of a paper airplane that is thrown in the classroom. Which statement best describes the path of the paper airplane?
The paper airplane will create a curved path toward the floor as it is pulled toward Earth's center.
A bowling ball collides with a pin and pushes the pin toward the right. Which describes the reaction force?
The pin pushes the bowling ball toward the left.
Which statement best explains why the overall charge on an atom is zero?
The positive charge of the protons in the nucleus equals the negative charge in the electron cloud.
When an experiment is replicated, how should the results of the two experiments compare?
The results of the experiments should be similar.
Which statements describe how chemical formulas, such as H2O, represent compounds? Check all that apply.
They show the elements that make up a compound. They show the types of atoms that make up a molecule. They show the number of each type of atom in a molecule.
How many dots belong in the electron dot diagram of a boron (B) atom?
Three
calculate the work done to lift a barbell weighing 100 newtons a distance of 1.5 meters
150 joules
pseudoscience
a process that involves the collection of information and ideas supported by belief or opinion
Momentum is always conserved in
A collision, either elastic or inelastic
Which describes a homogeneous mixture?
A solute dissolves in a solvent to make a solution.
The chemical symbol for the element calcium is Ca. What would be the symbol representing calcium atoms that have lost two electrons?
Ca+2
_______ investigations provide large amounts of information about a wide range of variables.
Comparative
is the property of matter in which a substance can transfer heat or electricity.
Conductivity
How many atoms of each element are in 4Na3PO4?
D. 12 sodium, 4 phosphorus, 16 oxygen
Substances A and B react in a ratio of A + B → AB. Colin was combining substance A and substance B to form substance AB. He added 10 g of substance A and 45 g of substance B. How much of substance AB would Colin make?
D. 55 g
Which statement describes a property of magnets?
D. Magnets attract or repel other magnets.
The atoms of which elements are least likely to form chemical bonds? Check all that apply.
Helium Neon Argon
The resistance that one surface or object encounters when moving over another. All moving objects are considered this. It acts at the surface where objects are in constant contact. There are four main types which are: static, sliding, rolling, and fluid
Friction
Which substances are acids? Check all that apply.
HBr CH3COOH H3PO4
Carl makes the table below to determine the number of atoms of each element in the chemical formula 4Ca(ClO3)2. What mistake did Carl make?
He did not multiply the chlorine and oxygen atoms by the coefficient 4.
Justin notices a particular type of caterpillar feeds only on cottonwood trees in his neighborhood.In which way has Justin increased his scientific knowledge?
He has made observations about the natural world.
Otis watches a cooking show on making mayonnaise. The chef dissolves salt and sugar in vinegar. She mixes in an egg yolk, and then mixes in oil until the ingredients are completely blended together. The chef says that it's great on sandwiches and that it can be stored without separating. Which best describes the purpose of the egg yolk in the recipe?
It acts to hold the vinegar and oil together in a colloid.
A ___ turns about a fixed point called a fulcrum.
LEVER
Large force over long time equals
Largest impulse
Units for average acceleration
M/s^2
Momentum
Mass in motion, inertia in motion
The process by which a solid changes to a liquid is?
Melting
Momentum is a measure of the ________ of an object.
Motion
Which best contrasts electric doorbells and audio speakers?
NOT A, D
Which phrase is not true about strong acids?
c. turn red litmus paper blue
A(n) _____ reaction is the rearrangement of atoms by breaking and reforming chemical bonds.
chemical
Making a pancake from batter is an example of a
chemical
During a test, what can a student use to identify what type and how many atoms are in a chemical compound?
chemical names
This is how sodium appears in the periodic table. The arrow is pointing to sodium's
combined number of neutrons and protons.
A synthesis reaction will produce a single .
compound
Which is the order of these solutions from strong acid to strong base? Solutions: household ammonia battery acid baking soda stomach acid antacid
battery acid stomach acid antacid baking soda household ammonia
How does a scientist use creativity?
by using prior knowledge to solve problems
A chemical reaction that has the general formula of AB → A + B is best classified as a _________ reaction.
decomposition
Brian made this table to organize his notes on changes of state. Which change of state has the wrong energy change listed?
deposition
Bohr
described atoms as having a positive nucleus with electrons that have different energies at different distances from the nucleus.
a change in position
displacement
Speed is calculated by taking ________ divided by time.
distance
The number at the end of an isotope's name is the________ number.
mass
What is conserved in physical changes?
mass
The amount of kinetic energy an object has depends on its ___.
motion
Which are limiting nutrients for plant growth?
phosphorus and nitrogen
What are two main purposes for using repetition when conducting experiments?
reducing mistakes and increasing confidence in results
A light bounces off the surface of a metal cup and shines in Harold's eyes. Which best describes what is happening to the light waves in this scenario?
reflection
Identify the basic unit of time in the SI and English Systems of measurement. seconds
seconds
Carla is using a fertilizer that contains nitric acid. How is nitric acid classified?
strong acid
Metals always retain their charges in a double replacement reaction
true
During which changes of state do atoms overcome the attractive forces between them?
vaporization and sublimation
the slope of a position versus time graph represents
velocity
View the model of the rover Curiosity. Which classification best applies to this model?
very complex
1897 worked with cathode ray tube and passed electricity inside empty glass tubes. He used magnets to pull the rays apart.
(JJ Thomson)
This mysterious glow "cathode rays" in the tube, he theorized were made of electrons.
(JJ Thomson)
Helium (He) and neon (Ne) are elements in Group 8A of the periodic table. How do the electron dot diagrams of these elements compare?
A. The electron dot diagram of helium has six fewer electrons than the electron dot diagram of neon.
A student uses red litmus paper to test the pH value of different solutions. Which would result in a color change of the litmus paper? Check all that apply.
drain cleaner soap
Which substance is used in lotions and cosmetics?
zinc hydroxide
Greg is giving a slide show presentation to a large audience. How might a laser best help him with the presentation?
B. He can use the laser to point to specific information on the slides.
Greg is in a bike race. At mile marker four (out of ten), his speed was measured at 13.5 mph. Which best describes the measured number?
B. It is the instantaneous speed of the bike rider.
Dominic made the table below to organize his notes about mixtures. What mistake did Dominic make?
C. Although it is possible to have more than one state, it is also possible to have only one state.
Which factors affect the strength of the electric force between two objects?
NOT D, A
A small, positively charged ball is moved close to a large, positively charged ball. Which describes how the small ball likely responds when it is released?
NOT D, B
A soccer ball is traveling at a velocity of 50 m/s. The kinetic energy of the ball is 500 J. What is the mass of the soccer ball?
NOT D. 0.5 kg
How many dots belong in the electron dot diagram of a boron (B) atom?
A. three
What else is produced during the combustion of propane, C3H8? C3H8 + 5O2 → 3CO2 + 4
H2O
Which question about dogs could be answered through scientific investigation?
How fast does an Australian terrier grow?
Which statement is not true about antacids?
c. help repair bone and cartilage
A bicycle has a momentum of 36 kg • m/s and a velocity of 4 m/s. What is the mass of the bicycle?
A. 9 kg
the newton is defined as the
force that can give a 1kg mass an acceleration of 1 m/s^2
Mercury's natural state is where the atoms are close to each other but are still free to pass by each other. In which state(s) could mercury naturally exist?
liquid
the first step in solving a physics problem is to
identify what the problem is asking
Lucy needs to lift a crate to a shelf 20 m high. She does 12,000 J of work on a machine to help her. The machine exerts a force of 500 N to lift the crate. What is the efficiency of the machine?
NOT B. 24%
A _____ solution is a solution with as much dissolved solute as it can hold at a given temperature.
saturated
A _______ solution is a solution with as much dissolved solute as it can hold at a given temperature.
saturated
Which factor is found in a scientific claim?
similar results in multiple tests of the claim
What is the property that is most similar among all elements across one whole period called?
the atomic mass
This is how fluorine appears in the periodic table. What information does "9" give about an atom of fluorine? Check all that apply.
the atomic number the number of protons the number of electrons
Scientists in a lab are working with two different samples of the element mercury. They know that the different samples are different isotopes. Which property of the isotopes must be different?
the mass number
Which is the best example of forces acting in the same direction?
two football players pushing a tackling sled
A stone tumbles into a mine shaft and strikes bottom after falling for 5.7 seconds. How deep is the mine shaft?
y= 159.4m
M(Vi - Vo) or I = F(T)
Impulse Formulas
The momentum change of an object is equal to the
Impulse acting on it
Momentum = Mass x Velocity
Momentum (formula)
A battery has chemical energy, which can be used to generate thermal and radiant energy in a lightbulb. Which best explains what happens to the amount of energy in this scenario?
C. The total energy in the system remains the same as the decrease in chemical energy equals the increase in thermal and radiant energy.
Metals are _________ because light reflects off the electrons.
shiny
scientific knowledge
the information that is gathered through the systematic study of nature
A stable atom that has a large nucleus most likely contains
more neutrons than protons.
Luis is helping his parents paint a border around the walls of a room. He uses a stencil to repeat the same design on each wall to form one long grapevine with a bunch of grapes every foot along its length. What type of chemical reaction does this best model?
polymerization
A scientist conducted an experiment and discovered that certain plants grow faster when given a particular amount of fertilizer. Another scientist conducted the same experiment and got similar results. Which concept does this best illustrate?
replication
What is the name of a solution whose concentration of solute is equal to the maximum concentration that is predicted from the solute's solubility?
saturated
the basic unit of time in both si and english system of measurement
second
Part of one row of the periodic table is shown. Which element's atoms have the greatest average number of neutrons?
selenium (Se)
Which uses direct current?
B.
Which of these is a compound?
B.) CO2
What mistake did Kamala make?
NOT C, B
--
--
When parallel light rays exit a concave lens, the light rays ____.
DIVERGE
kg•m/s.
Momentum (SI unit)
A football player has a mass of 65 kg and is moving with a velocity of 5 m/s. What is the player's momentum?
325 kg • m/s
What else is produced during the combustion of butane, C4H10?
8CO2
a 60 kg person travels to the moon where the value of gravity is 1.6N/kg. what is the persons weight?
96 N
A baseline for an experimental investigation is provided by the hypothesis .
<<<<
Experimental investigations allow for the control of variables.
<<<<
When balanced, which equations would have the coefficient 3 in front of the first set of atoms? Check all that apply. A. AgBr + GaPO4 → Ag3PO4 +GaBr3 B. H2SO4 + B(OH)3 → B2(SO4)3 + H2O C. Fe + AgNO3 → Fe(NO3)2 + Ag D. C2H4O2 +O2 → CO2 +H2O
A
Which clue can be used to identify a chemical reaction as a combustion reaction?
A hydrocarbon reacts with oxygen.
If peers accept a scientific paper's claim, what is the next step in the process?
A journal will publish the paper.
Experiment
A scientific procedure to make a discovery
Momentum is
A vector, which means it has a magnitude and direction North and East - Positive South and West - Negative
Which best compares simple machines with compound machines?
A. Both make work easier, but compound machines consist of two or more simple machines.
Which contains the particles that are vibrating fastest?
A. boiling water
Food can spoil very quickly. Which methods are used to minimize the reactions that allow bacteria and fungi to grow?
A. preservatives and low temperature
recoil
Acceleration
Which example best illustrates that light behaves like particles?
B. Light bounces off a white cement sidewalk.
The magnets are released and swing freely. Which diagram best predicts their final position?
C.
Which labels best complete the diagram?
D.
The compound magnesium phosphate has the chemical formula Mg3(PO4)2. In this compound, phosphorous and oxygen act together as one charged particle, which is connected to magnesium, the other charged particle. What does the 2 mean in the formula 5Mg3(PO4)2?
D. There are two phosphate ions in a molecule of magnesium phosphate.
Which type of reaction is NaCl + AgNO3 → NaNO3 + AgCl?
D. replacement
Which statement best explains why objects are pulled toward Earth's center?
Earth has a much greater mass than objects on its surface
Which statement describes how Earth compares to the moon?
Earth has more inertia than the moon.
Which best describes the reliability of the source?
Editorial blogs are considered an unreliable source because the author may not have a science background.
Which statement describes Newton's law of universal gravitation?
Every object in the universe attracts every other object
Xander was traveling at a final velocity of 4.5 m/s for 3.5 seconds. Finley was traveling at a final velocity of 3.6 m/s for 4.2 seconds. Max was traveling at a final velocity of 7.3 m/s for 1.2 seconds. They all started from the same location. Which lists them from least to most acceleration?
Finley, Xander, Max
The graph indicates the running route for Tobias. Which best describes his run?
From time 6 to 10, he was at his slowest.
Mass is a measurement of the amount of matter something contains, while Weight is the measurement of the pull of gravity on an object.
How is mass different from weight?
Sharon reads two different articles about avocados. The first article, in a weight loss magazine, claims that avocados are unhealthy because they are high in fat. The second article, in an annual publication from a doctors' group, claims that the fat in avocados is a type that is good for the heart. To assess these claims, which question(s) might Sharon ask? Check all that apply.
Is the source of this claim reputable? Is the source an authority on the subject?
Which is a characteristic of the part of the atom marked "B"?
It is negatively charged.
p = mv. If the mass is doubled and the velocity doubled, what happens to the momentum?
It quadruples
Which statement describes a newton?
It reflects the amount of force an object exerts
The SI symbol for volume is .
L
Kinetic energy is the energy an object has as a result of its ___.
MOTION
A coherent, typically large body of matter with no definite shape
Mass
Which would ultimately cause the armature in an electric motor to spin?
NOT A. The current in the armature stops.
A light ray hits a hard, opaque object. The angle at which the light ray bounces off the object depends on
NOT A. the smoothness of the surface.
Which type of waves can be used to clear a blockage from small tubes in the kidneys?
NOT B, D
Which change increases the electric force between objects?
NOT C, D
The slope and shape of the graph describes what?
Objects motion
Is the friction that exists between a stationary object and the surface on which it's resting. It always acts in the direction opposite to that of the applied force. You experience it every time you take a step
Static Friction
Which elements have fewer than four dots in their electron dot diagrams? Check all that apply.
Strontium Gallium
Giovanni created this chart to study for an exam. Which best describes how to correct the error in the chart?
Swap the uses for iron oxide and calcium carbonate.
This is how manganese appears in the periodic table. The arrow is pointing to the atomic of manganese.
Symbol
Micah knows that a car had a change in velocity of 15 m/s. To determine acceleration, Micah also needs the _____ of the total trip in seconds.
TIME
English System
The English set of units
Energy
The ability to cause change
If the time is increased, what happens to the force that stops your momentum?
The force decreases.
A scientist on Earth drops a hammer and a feather at the same time an astronaut on the moon drops a hammer and a feather.
The hammer hits the ground before the feather on Earth, and the hammer and feather hit at the same time on the moon.
Which statement about the physical change of liquid water boiling into steam is true?
The heat added represents an energy change.
Dmitri Mendeleev and Henry Moseley developed their periodic tables about forty years apart. During that time, many discoveries in chemistry were made. Which fact was most likely discovered between the time of Mendeleev's table and the time of Moseley's table that helped Moseley develop his version?
The number of protons in an atom is different than the atom's total mass.
When liquid gold becomes a solid, its particles get closer together. Which best describes what happened to the gold?
The rearrangement of particles in a physical change
Renald completed only one trial of his experiment. What effect will this most likely have?
The results are more likely to have errors.
What has more momentum, a car traveling at 30 m/s or the same car traveling at 60 m/s?
The second one because it's going faster
Cobalt is a metal. Which best describes the cobalt atom and its interactions with other cobalt atoms?
The valence electrons are weakly attracted to the protons and move amongst the atoms.
Dependent Variable
The variable that changes due to the independent variable
Roberto creates an animation titled "Flying through an Atom." The animation makes it seem as if the viewer passes all the way through an atom, starting from one side, then through the atom's center, and then leaving through the other side. What is the best description of the order of events in the animation?
The viewer travels through the electron cloud, then the nucleus, and then the electron cloud again.
Which force best represents Fg?
The weight of a barbell acting on a weight lifter is 80 N.
Julianna blows air into a balloon to inflate it. What can be known about the atoms of the air?
They are moving constantly at high speeds
Which statement best describes the difference between endothermic and exothermic reactions?
They are opposites because endothermic reactions require energy and exothermic reactions release energy.
Which statement best describes the atoms in a gas?
They move freely in all directions
Often, the forces on an object are unbalanced. An unbalanced force is a force that results when the net force acting on an object is not equal to zero. When an unbalanced force acts on an object, the object accelerates
Unbalanced Forces
Which acids are naturally found in foods and can be safe to eat? Check all that apply.
acetic acid citric acid
Which example illustrates a chemical change?
burning wood
Which factors affect the electrical force between two objects?
charge and distance between them
Which is most likely a physical change?
cutting a substance into four pieces
Choose the correct equation for the reaction of HBr with Ca(OH)2.
d. 2H₃O+ + 2Br⁻ + Ca²⁺ + 2OH⁻ → 4H₂O + 2Br⁻ + Ca²⁺
An equivalence point can be reached during the titration of a
d. All of the above
Which base is a weak electrolyte?
d. ammonia
Acids are substances that
form hydronium ions when dissolved in water.
During which changes of state does the motion of the atoms decrease?
freezing and condensation
a tentative, testable statement that attempts to explain a set of scientific observations
hypothesis
What is an example of a physical change?
ice forming and then melting back into water
What should be the ending of the second element in a covalent compound?
ide
newtons first law is also known as the law of
inertia
if an object is accelerating, what wont occur
it remains motionless
Yogurt is made by changing
lactose (milk sugar) into lactic acid.
Which laboratory activities involve chemical changes? Check all that apply.
leaving a copper penny in vinegar until it turns green putting an iron nail outside for a month and observing changes
Which substance, when added to milk, causes the milk to curdle?
lemon juice
Which is the order of these solutions from strong acid to strong base? Solutions: household ammonia battery acid baking soda stomach acid antacid
not battery acid stomach acid baking soda antacid household ammonia battery acid stomach acid antacid baking soda household ammonia
In what part of the atom is most of the mass located?
nucleus
A company has a volume of contaminated water that needs to be separated through evaporation. What would allow the mixture to be separated in the shortest time?
placing the water in several shallow pools in a sunny spot
Which uses of iron are due to its chemical properties? Check all that apply.
producing colored sparks in fireworks and rusting in the presence of water and oxygen
A chemical reaction is the only way to separate a(n) _ .
pure Substance
View the spinner. In which area is it impossible to land?
purple
Which acid-base reaction will yield a neutral solution?
strong acid-strong base
A substance with a pH of 13 is
strongly basic.
on the way to a concert, john stops at the mall to buy some camera film. if you divide the distance he travels to the concert by his average speed for the entire trip, you are calculating what
time interval
The Port of Houston is one of the busiest ports in the country. The U.S. Department of Energy gave this port $3.4 million to operate twenty heavy-duty hydrogen hybrid fuel cell powered trucks around the port. Which is the most likely reason the U.S. government made such an investment?
to reduce harmful emissions
What is the molarity of a strong acid solution with a pH of 2?
1 × 10⁻² M
Which equations can be used to solve for acceleration? Check all that apply.
1, 4, 6 and 7
lifting a 70-kilogram barbell 2.0 meter above the floor increases its potential energy bu about
1,400 joules
View the spinner. What is the probability that the spinner will land on a red section of the circle? Enter your answer as a fraction.
1/5
A toy car is placed at 0 on a number line. It moves 9 cm to the left, then 4 cm to the right, and then 6 cm to the left. The total distance the toy car traveled is ____ cm
19
A 0.00001 M solution of the strong acid HCl has a pH of
5
Gymnast lands on a padded mat causing an increase in time by 5, the force on her body is
About 5 times less
_____________ is the rate of change in velocity.
Acceleration
Which statements are true of all scientific endeavors? Check all that apply.
All scientific endeavors are supported by evidence. All scientific endeavors are a systemic process. All scientific endeavors involve observation. All scientific endeavors involve experimentation. All scientific endeavors involve the collection of information.
Which statement correctly describes whether a compound is a pure substance?
B. A compound is a pure substance because its molecule cannot be broken down into simpler particles by physical means.
Which describes a homogeneous mixture?
B. A solute dissolves in a solvent to make a solution.
Which best explains how fiber-optic technology has improved communication?
B. It has allowed for faster transmission of Internet signals.
When Object 1 came into contact with Object 2, Object 2 got warmer. What can be concluded about the objects before they came into contact with each other?
B. Object 1 had faster-moving particles.
Aansi wants energy on a sound wave to be carried more quickly through a metal medium. Which could she do?
B. increase the temperature
Dominic made the table below to organize his notes about mixtures. What mistake did Dominic make?
Although it is possible to have more than one state, it is also possible to have only one state.
Who is known as the "father of modern chemistry" because he first organized all known elements into four different groups?
Antoine Lavoisier
When discussing Newton's laws of motion, which terms do people most likely use when talking about Newton's third law of motion?
"action" and "reaction"
Which wire, when current flows through it, would be surrounded by the strongest magnetic field?
C.
How many neutrons does this atom have?
C. 6
Which object absorbs the most visible light?
C. a black t-shirt
Which of these is a compound?
CO2
Two objects bounce off each other.
Elastic collision
The amount of kinetic energy possessed by a 0.3 kg ball rolling at a speed of 4 m/s is how much?
Ex= 2.4J
If Suzie doubles her sprinting velocity, what else doubles? p = mv
Her momentum
The _____ the temperature of the solvent, the more quickly the solute will dissolve.
Higher
Four students are analyzing four different substances and recording their findings in this table. Which most describes this table?
Leonna has a solid, Xiao has a liquid, Blake made a mistake, and Amir has a gas.
Momentum deals with
Newton's third law
Both Kinetic Energy and momentum are conserved
Perfectly Elastic Collision conserves
Potential Energy
Stored energy of position
Newton
The S.I. unit for force
Which statement best describes the atoms in a solid?
They are held together by strong attractions.
What is the correct classification of a mixture in which both a solid and a liquid are visible?
a heterogeneous mixture and a suspension
Which model is most likely used to predict a future event?
a model of weather systems
Force
a push or pull
When is a detergent more useful for cleaning than a soap?
cleaning in hard water
What is the constant for gravity?
g=9.81 m/s2
Which source is reliable?
government websites
A base forms which ions in solution?
hydroxide
Mixtures can be separated because the components have different _____ properties.
physical
Which formula can be used to express the law of conservation of momentum, where p = momentum?
pi = pf
Putting lemon juice on a piece of cut apple will
prevent the fruit from turning brown.
To calculate the velocity of an object, the ____________ of the position vs time graph should be calculated.
slope
How would you calculate the slope on a graph?
slope= rise/run
The anion in a soap contains a
sodium or potassium ion.
Ions that do not change during a chemical reaction are called
spectator ions.
Which term best describes all atoms in ionic bonds?
stable
Which type of reaction is Mg + S → MgS?
synthesis
Which element's symbol could replace the question mark in the diagram?
tellurium (Te)
The equation below is for potassium oxide. 4K + O2→ 2K2O The ratio of atoms of potassium to ratio of atoms of oxygen is
2:1
what impulse must be applied to a 3-kilogram object starting at rest to give is 150 joules of kinetic energy?
30 newton-seconds
What is the momentum of a 5 kg object that has a velocity of 1.2 m/s?
6.0 kg • m/s
Which is the best description of a molecule?
A molecule of a compound is composed of at least two types of atoms.
Which statement describes all chemical changes, but not all physical changes?
A new substance forms.
Which statement describes the relationship of voltage and current?
A.
What is a solenoid?
A. a current-carrying wire with many coils
What does the 4 mean in the formula 4Na2SO3?
C. There are four molecules of sodium sulfite.
Which substances are bases? Check all that apply.
Ca(OH)2 RbOH
If calcium carbonate (CaCO3) decomposes, what would the product of the reaction be? CaCO3 → ___ + CO2
CaO
Momentum notes
Every moving mass has it -inertia in motion
Where are alkaline earth metals found on the periodic table?
Group 2
If data is faked or is misplaced, it is
Invalid
In what way is Model A better than Model B?
Model A shows the three-dimensional shape of the molecule, but Model B does not.
p
Momentum (symbol)
Which best explains what will happen if Sharilyn lifts a bag with the straps placed in the middle of her forearm instead of lifting the bag using her hand?
NOT C. The bag will be easier to lift because it is farther from the fulcrum and the mechanical advantage will be greater.
The SI unit of force. It is equal to the force that would give a mass of one kilogram an acceleration of one meter per second per second, and is equivalent to 100,000 dynes. Force is measured in this, abbreviated as N. 1 N is equal to 1 kilogram-meter per second squared (1 N = 1 kg*m/s2). The Newton is named after Sir Isaac Newton
Newton
Which is a pure substance?
Nitrogen
Based on the replacement reaction, what would the products of the reaction be? BeSO4 + 2NH4OH → Be(__)2 + (NH4)2SO4
OH
Which objects would sink in honey, which has a density of 1.4 g/cm³? Check all that apply.
Object 2 (1.5g /cm³) Object 4 (2.3 g/cm³) Object 5 (4.1 g/cm³)
Elastic collision
Objects bounce off one another without any deformation, sound, or generating heat
Why are bacteria a necessary part of the nitrogen cycle?
Other living things cannot use atmospheric nitrogen.
If forces acting on an object are unbalanced, the object could experience a change in ____ , direction, or both.
SPEED
Which statement is represented by the graph?
Temperature can change the solubility of a solute.
The Statue of Liberty is made of copper that has turned green because it has undergone a change. What can be said about this change?
The change is not a physical change because a new chemical is formed on the outside of the statue.
Helium (He) and neon (Ne) are elements in Group 8A of the periodic table. How do the electron dot diagrams of these elements compare?
The electron dot diagram of helium has six fewer electrons than the electron dot diagram of neon.
Laura wonders why an object can ever accelerate if every force it exerts causes a reaction force. Which explanation best answers her question?
The forces are not exerted on the same object, so they are not balanced forces.
Which action results from the combination of gravity and inertia working on the moon?
The moon's orbit around Earth
Independent Variable
The variable that you change
Which force best represents Fg?
The weight of a barbell acting on a weight lifter is 80 N
weight is the force of gravity on an object
True
Carlie rides her bicycle 5.2 km up a steep hill in 7 minutes. What is her speed?
V= 0.74 km/min
Radiation transfers thermal energy through ____.
WAVES
Collision
When 2 or more objects come together (one must be moving)
Even though every action has an equal and opposite reaction force, they do not cancel one another and motion may still occur because the
action and reaction forces are applied to different objects
A metal oxide reacting with water will synthesize a(n):
base
An ionic bond forms between sodium and chlorine when the sodium atoms ____ electrons.
donate
Work
force times distance
1A, 3B, and 7A are examples of on the periodic table.
groups
the impulse applied to an object is equal to the change in the objects
momentum
Covalent Compound _____ conduct electricity well
rarely
Which change of state is shown in the model?
sublimation
The graph below shows how solubility changes with temperature. mc024-1.jpg A solution is made that contains 20 g of Ba(NO3)2 at 60°C. How would this solution be classified if it were cooled to 40°C?
supersaturated
systematic
using a planned or careful method
Collision
when two objects hit
The resulting net force of an object is represented below. →10 N Which most likely represent the forces acting on the object?
← 63 N and → 73 N
At the equivalence point of a strong acid-strong base titration the pH is
7.
The model below shows an atom of an element. What is the atomic number of this atom?
8
Which statement best describes the work and energy in these examples? Example 1: Running a car requires gas. Example 2: Humans require food to live.
A. The gas and food are examples of energy.
Which property of the coating on fiber-optic strands makes light visible only at the ends of the strands?
A. reflectivity
Which best explains how to correct Savion's error?
B. Reorder the steps so that step 4 appears before step 3.
During which step does the robotic arm do work on the block?
B. Step 2
Which change of state is shown in the model?
B. boiling
Momentum is increased when
Both mass and velocity are increased
What is the speed of a wave with a frequency of 2 Hz and a wavelength of 87 m?
D. 174 m/s
Kiley went 5.7 km/h north and then went 5.8 km/h west. From start to finish, she went 8.1 km/h northwest. Which best describes her numbers?
D. 5.7 km/h north and 5.8 km/h west are instantaneous velocities, while 8.1 km/h northwest is the average velocity.
Two double bonds means that the total number of electrons being shared in the...
D. 8
Georgia moves an unattached piece of wire back and forth over a magnet. Which best explains what will happen?
D. A current will not be induced because the wire is not part of a closed circuit.
Which scenario best describes an object with a displacement of zero?
D. A race car starts and ends at the same point on a track.
Any radiation treatment has the potential to damage DNA in healthy cells. Which lists therapeutic uses of radiation based on the likelihood of affecting healthy cells in order from least likely to most likely?
D. radiopharmaceuticals, brachytherapy, deep external beam radiation therapy
Which type of reaction has the general formula of AB + CD → AD + CB?
D. replacement
Which is a valid velocity reading for an object?
D. 45 m/s north
The combination of an initial forward velocity and the downward vertical force of gravity causes the ball to follow a curved path.
Describe why a projectile follows a curved path.
Which factor affects the force of gravity between objects? Check all that apply.
Distance Mass
Kinetic Energy
Energy of motion
Lifting a 50 kg barbell 2.0 meters above the floor increases its potential energy by how much?
Ep=981J
Emmett is lifting a box vertically. Which forces are necessary for calculating the total force?
Fp and Fg
This chart represents four famous scientists and an aspect of their contributions. Which scientist was the most creative?
Gutenberg
The equation shows reactants to a neutralization reaction. Ca2+ + OH- + H+ + NO Which describes what will happen to the H+ when these reactants form products?
H+ binds with OH- to make water.
Superman and asteroid are both at rest in space, if superman throws the asteroid and it flies away at 8 m/s what will happen to him?
He will fly away faster
Which best describes the negative impact of human water use?
Increased runoff carries fertilizers.
The Venn diagram compares protons with electrons. Which shared property belongs in the region marked "B"?
Is electrically charged
For an object moving with constant acceleration, the average velocity is equal to what?
Is equal to the average of the initial velocity and the final velocity
Eli states that sodium phosphate is a mixture because it is composed of both sodium ions and phosphate ions. Which is the best analysis of Eli's statement?
It is incorrect because sodium phosphate is a compound that has a single composition.
What does the chemical formula C3H6O2 tell about a molecule of the compound it represents?
It is made up of 11 total atoms of 3 different elements.
Worked with Earnest Rutherford. Credited with discovering the neutron. His discovery completed the atomic model.
James Chadwick
______ energy is the energy an object has because of its motion.
Kinetic
Momentum can be defined as "mass in motion." All objects have mass; so if an object is moving, then it has momentum - it has its mass in motion.
Momentum (defined)
Which best labels the chart?
NOT A. Title 1 is "Longitudinal Waves," and Title 2 is "Transverse Waves."
When an object slows down what does the average acceleration look like?
Negative average acceleration or deceleration.
PLANETARY MODEL
Neils Bohr
A chemical reaction is the only way to separate a(n) ______.
PURE SUBSTANCE
Which describes a scientist being creative?
Sara tries turning a test tube upside down to collect a gas.
While doing a distillation, Farha heats the mixture too fast, and the temperature rises too quickly. If the mixture is composed of two liquids, how will this likely affect the separation of the mixture?
Some liquid with the higher boiling point will be collected along with the liquid with the lower boiling point.
How does an atom change if all of its electrons are removed?
The atom becomes positively charged.
Which statements describe Rutherford's model of the atom? Select all that apply.
The atom is mostly empty space. Electrons orbit around the center of the atom. The atom's positive charge is located in the atom's nucleus.
If a chemical reaction does not reach its activation energy, which will most likely occur?
The chemical bonds will remain unchanged.
Identify the reaction type shown and describe the clues that were used to identify it. NH4NO3 → N2O + 2H2O
This chemical equation represents a decomposition reaction. This identification is based on the fact that the single reactant chemical compound breaks down into two different chemical substances that are different from the initial chemical substance
In an element's square on the periodic table, the number with the greatest numerical value represents the
atomic mass.
Atoms of two different elements must have different
atomic numbers.
Which solution has the greatest number of hydroxide ions?
baking soda, pH = 9
if he net force acting on a moving object is 0, what will the object do?
continue in the same direction with no change of speed
robin measures the force needed to pull a wagon up an incline as more weight is added. in this investigation weight is the ~what~ variable?
control
Which method can be used to separate the components of a solution? Check all that apply.
evaporation distillation
what is NOT a metric measurement
foot
The type of chemical bond that involves the transfer of electrons between atoms is a(n) _ bond.
ionic
Which lab involves a chemcial change?
leaving a copper penny in vinegar until it turns green putting an iron nail outside for a month and observing changes
An acid or a base dissolved in water breaks down into a positive and a ion.
negative
Which substance is used in fertilizers?
nitric acid (HNO3)
calculate the momentum of a 2300kg car traveling at 25 m/s.
p= 57500 kg.m/s
What is produced during the double replacement reaction of Ba(NO3)2 and Na2SO4?
2NaNO3 + BaSO4
Who described atoms as small spheres that could not be divided into anything smaller?
Dalton
Change in momentum
Impulse
Which element is magnetic?
D. cobalt
If nothing moves, then how much work is done?
None
an object is dropped from rest and falls downward for 3 seconds. what is its average speed
14.7 m/s
What is the weight, on Earth, of a book with a mass of 1.5 kg?
14.7 N
Which statement is best supported by the information in the chart?
B. Atom X will accept electrons from Atom Y.
Give an example of an Inelastic collision.
An egg splats on the floor Permanent change in shape sound energy released objects stick together
What could be put into the center section of this Venn diagram?
B. "Carry energy" and "Follow a pattern"
Den pushes a desk 400 cm across the floor. He exerts a force of 10 N for 8 s to move the desk. What is his power output? (Power: P = W/t)
B. 5 W
If a catalyst lowers the activation energy, a(n) _______ raises the activation energy.
inhibitor
How many atoms of each element are in 4Na3PO4?
12 sodium, 4 phosphorus, 16 oxygen
A bowling ball has a mass of 7.2 kg and a weight of 70.6 N. It moves down the bowling alley at 1 m/s and strikes a pin with a force of 15.0 N. What is the force that the pin exerts on the bowling ball?
15.0 N
a professional golfer walks at an average rate of 3.20 feet per second on the gold course. the amount of time required for her to walk from the tee to a green 612 feet away is
191 seconds
How many atoms of nitrogen are in the chemical formula Ni(NO3)2?
2
The equation for water is H2 +O2 → H2O. To balance the equation, which coefficient should be placed in front of H2 and H2O?
2
Which most likely could cause acceleration? Check all that apply.
2. wind 3. watermovement 4. a hill 5. a stop light
a roller coaster traveling at 4 m/s speeds up to 14 m/s in 2 seconds as it goes down a hill. what is the acceleration
5 m/s
The model below shows a calcium atom. How many electrons are in the third energy level?
8
Distance
An amount of space between 2 things
Which statement describes an atomic nucleus?
An atomic nucleus contains most of the atom's mass.
Holden is trying to determine the velocity of his race car. He went 20 meters east, turned around, and went 40 meters west. He turned the car one more time and went 35 meters east. His car was 15 meters from the starting line. This took 5 seconds. What is the car's velocity?
B. 3 m/s east
If the change in velocity increases, what happens to the acceleration during the same time period?
B. Acceleration increases.
Which two wire properties would provide the greatest resistance to the flow of a current?
B. long, thin
Which should he write in the "Use" section for X-rays?
B.luggage inspections
A force that holds atoms together is a chemical ___
BOND
Which is the best description of a molecule?
C. A molecule of a compound is composed of at least two types of atoms.
Which event always involves a chemical change?
Burning
Which example illustrates a chemical change?
Burning Wood
The chart shows the times and accelerations for three drivers. Which lists them from greatest to lowest change in velocity?
D. Kira → Diego → Dustin
Which is a property of every mixture?
D. One substance can be separated from another through physical means.
When an electric circuit operates, a buzzer makes a sound. What happens to the electric charges in this circuit?
D. The electric charges move from the energy source through the buzzer and back to the energy source.
Laura wonders why an object can ever accelerate if every force it exerts causes a reaction force. Which explanation best answers her question?
D. The forces are not exerted on the same object, so they are not balanced forces.
Julie takes a cold glass of clear, colorless liquid out of the refrigerator and puts it on the table. As the liquid warms up to room temperature, Julie sees bubbles of gas form in the liquid and rise to the surface. Which conclusion is best supported by Julie's observations?
D. The liquid is a mixture because it has a gas dissolved in a liquid.
An endoscope is a fiber-optic medical instrument that emits light. Doctors can insert endoscopes into hollow body parts. Which property of fiber-optic strands makes them most useful in endoscopes?
D. They are small and flexible.
Which is the balanced equation for V2O5 + CaS → CaO + V2S5?
D. V2O5 + 5CaS → 5CaO + V2S5
Which answer choice provides the best set of labels for Wave A and Wave B?
D. Wave A: Low Frequency Wave Wave B: High Frequency Wave
Which labels best complete the diagram?
D. X: Low potential energy Y: High potential energy Z: Flow of electrons
Earth's gravity acts downward toward the center of Earth.
Earth's gravitational force acts in what direction?
Which object requires the greatest change in momentum in order to stop its motion?
D. Z
Which best describes the object on the right?
D. a bar magnet with its south pole on the left
Which best describes the order of the technology used to transmit a sound through the radio?
D. microphone → transmitter → radio
Which is most likely a covalent compound?
D. CF4
Which ray would appear on a ray diagram for both a concave lens and a convex lens?
D
Acceleration involves a change in speed or
Direction
Acceleration has what two things?
Direction and magnitude
Chadwick
Discovered the neutron and worked on the atomic bomb
Calculating average velocity
Displacement divided by the time interval
Metallic bonds are important to how paperclips are both made and used. Which statement best describes how metallic bond properties are important for making and using paperclips?
Ductility is important for making paperclips, and malleability is important for using them.
In the absence of external forces, momentum is conserved in
Either elastic or inelastic collisions
Velocity with constant acceleration equation
Final velocity equals initial velocity + acceleration times time interval
Final velocity after any displacement
Final velocity squared equals initial velocity squared + 2 times acceleration times displacement
Force that opposes motion between two surfaces.
Friction
What else is produced during the combustion of propane, C3H8? C3H8 + 5O2 → 3CO2 + 4
H2O
A force can cause a resting object to move, or it can accelerate a moving object by changing the object speed or direction.
How is the motion of an object affected when a force acts on it?
The sum of potential and kinetic energies in the particles of a substance is called _______ energy.
INTERNAL
When water (H2O) freezes into ice, some of the properties have changed but the ________ of the H2O is the same.
Identity
A body at motion stays in motion unless acted on by an outside force and a body at rest stays at rest.
Inertia
Which best describes the current model of the atom?
It may be revised with increasing scientific knowledge.
p = mv. If the mass is triples what happens to the momentum?
It triples
For a collision occurring between object 1 and object 2 in an isolated system, the total momentum of the two objects before the collision is equal to the total momentum of the two objects after the collision
Law of conservation of momentum
Two models of the same compound are shown. In what way is Model B better than Model A?
Model B shows how the atoms in the molecule are connected, but Model A does not.
Which information makes this article reliable?
More than 50 studies were conducted.
In the equation for final velocity after any displacement, you must take one of the right side of the equation to find the final velocity?
Must take square root
Lana balanced an equation so that the result was 2C2H3Br + 5O2 → 4CO2 + 2H2O + 2HBr. Which most likely represents the starting equation?
NOT 2C4H3Br + 5O2 → 4CO2 + 2H2O + 2HBr NOT C4H3Br + O2 → CO2 + H2O + HBr
Which simple machine is shown in the diagram?
NOT A, C.
Which is a property of every mixture?
One substance can be separated from another through physical means.
is a process that involves the collection of information and ideas supported by evidence.
Science
Fluorine has an atomic number 9. It is in period 2 of the periodic table. The diagram shows the electron dot diagram of a fluorine atom. How many valence electrons are in an atom of fluorine?
Seven
Zora wants to dissolve a solute in a solvent quickly. Which best describes what she should do?
Shake it repeatedly
Hee Sun drew an electron dot diagram of a silicon atom as shown. In addition to changing the symbol to C, how would this diagram compare with an electron dot diagram of a carbon atom (C)?
The same number of dots would appear in the diagram for carbon.
a penny dropped into a wishing well reaches the bottom in 2.4 seconds. What was the velocity at impact
V2=23.5 m/s
Which instrument is best suited for measuring the dimensions of a shoebox?
a ruler
Choose the correct equation for the reaction of HNO₃ with KOH.
a. H₃O⁺ + NO³⁻ + K⁺ + OH⁻ → 2H₂O + K⁺ + NO³⁻
Which example best represents balanced forces?
an elevator stopped on the third floor
Which statement is not true about bleach?
c. removes the substance causing a stain
Tony gets stung by an ant. He applies baking soda, a weak base, to the site. What acid is Tony neutralizing with the baking soda?
formic acid
Serena is mixing a material into a beaker filled with a liquid. She notices that the material seems to disappear into the liquid. What physical property of the material is Serena most likely observing?
solubility
the inertia of 2 objects must be the same if
the same force causes the same acceleration in both objects
A scientist is examining an unknown solid. Which procedure would most likely help determine a chemical property of the substance?
exposing it to a flame to see if it catches on fire
Sonya is studying a nonmetal element. She learns that the element is like other elements in its group because it can bond to form a salt or an acid. She also learns that the element is the most reactive element in its group. Which element is Sonya most likely studying?
fluorine (F)
What is an example of an English measurement that is NOT used in the Metric system?
foot, inch, quart, gallon, etc.
a push, pull, or other action that has the ability to change motion is called a
force
in science work is defined as
force x the distance moved in the same direction as the force
What else is produced during the combustion of propane, C3H8?
h2O
Covalent bonds are formed between ______
nonmetals
Who would most likely be required to work with sodium hydroxide?
plumber
A proton has ______charge.
poitive
A chemical reaction that has the general formula of nA → (A)n is best classified as a______ reaction.
polymerzaton
The idea that people behave in odd ways on a full moon is an example of
pseudoscience.
Gold's natural state has a definite shape and a definite volume. What is gold's natural state(s)?
solid
What is 0.000345 expressed in scientific notation?
3.45 × 10-4
A student combined equal amounts of two solutions. One solution had a pH of 2 and the other had a pH of 12. Which would most likely be the resulting pH?
6
Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below. What experimental evidence led to the development of this atomic model from the one before it?
A few of the positive particles aimed at a gold foil seemed to bounce back.
Rutherford used positively charged particles to investigate the structure of the atom. The results surprised him, and he developed the atomic model shown below. What surprising result is explained using this model?
A few positive particles bounced back because they were pushed away from the positive center.
Inertia
An objects resistance to motion
In which reaction would the activation energy result in an endothermic reaction?
B. an egg cooking
What is the chemical formula for the molecule modeled?
C. C6H12O2
How does radiation help treat cancer?
C. It heats up the cancer cells and weakens them.
Which part of the electromagnetic spectrum is typically used to make images based on the temperatures of objects?
C. infrared light
Identify the reaction type shown and describe the clues that were used to identify it. Fe2O3 + 2SiO2 → Fe2Si2O7
This chemical equation represents a synthesis reaction. This identification is based on the fact that the reactant chemical compounds combine to form a single chemical substance that is different from the initial chemical substance.
The diagram shows Ned's movement as he left his house and traveled to different places throughout the day. Which reference point should be used to find out how far Ned traveled when he went from the pet store to the swimming pool?
W
When you ride a bike at full speed, which has a greater momentum, you or the bike?
You
A machine called a centrifuge is used in _____.
-separation by density
One half of a balanced chemical equation is shown. 3Mg(OH)2 + 2H3PO4 Which lists the numbers of each atom the other half of the equation would contain?
3 Mg, 2 P, 14 O, 12 H
Nina is working with electricity and shortens the wires through which the current is flowing. What is Nina most likely trying to accomplish?
decrease resistance
as the speed if a moving object doubles, the amount if mechanical kinetic energy that it possesses
decreases by four times
When force is measured in newtons and distance is measured in meters, the work done is measured in
joules
What best explains whether bromine (Br) or neon (Ne) is more likely to form a covalent bond?
A. Bromine forms covalent bonds because it has seven valence electrons, but neon has eight valence electrons and already fulfills the octet rule.
Alice added sodium chloride to water and stirred the water for several minutes. Alice is most likely trying to demonstrate that ionic compounds
B. can dissolve.
Teeth are an example of which type of simple machine?
B. wedge
Look at the graph below. Which type of graph is displayed?
Bar
Based on the reaction, identify the products. BeF2 + Mg → MgF2 + __ What type of reaction does this represent?
Be replacement
During an inelastic collision, the resultant velocity will
Be slower because the mass increases
According to Dutch scientist Christiaan Huygens, what was light made of?
C. waves
The resulting net force of an object is represented below. →10 N Which most likely represent the forces acting on the object?
C. ← 63 N and → 73 N
The graph represents velocity over time. What is the acceleration?
C. 0.2 m/s2
Based on the position vs. time graph, which velocity vs. time graph would correspond to the data?
C. the one going horizontal
How are the magnetic field lines near the south pole of a magnet affected when a second south pole is brought near it?
NOT B, C
Which conclusion is best supported by the information in the chart?
NOT C. Material X is more reflective than material W.
What error did Laticia make?
NOT C. The arrows to the left of Earth should point down.
When a car comes to a full stop after hitting a brick wall and hitting a water filled barrel, the change in momentum is: greater hitting the wall, greater hitting the barrel, the same momentum change in both.
The same momentum change in both.
There are several different models that represent compounds. One type of model is shown. What type of model is shown?
a ball-and-stick model
Which tools measure the volume of liquid? Check all that apply.
a graduated cylinder a pipette a beaker
Which material is the least likely to be recognized as a mixture by looking at it under a microscope?
a homogeneous mixture
Which most likely describes a supersaturated solution?
a hot solution with all of the solute dissolved
A positively charged object will attract an object that has ____.
a negative charge
Which best describes a neutralization reaction?
a reaction between an acid and a base
Which will settle out if allowed to sit on a table?
a suspension
the slope of a velocity versus time graph represents
acceleration
Which type of replacement reaction is 2NaOH (aq) + H2SO4 (aq) --> Na2SO4 (aq) + 2H2O (l)
acid-base neutralization
According to Newton's third law of motion, which are equal?
action force and reaction force
The minimum amount of energy required to start a chemical reaction is the _______ energy.
activation
The modern periodic table has 18 groups. This is how osmium appears in the periodic table. Rounded to the nearest whole number, how many neutrons, on average, are in an atom of osmium?
114
a digital timer displays a reading or 3:23:47. in seconds, this display represents how many seconds
12,227
One isotope of sodium has 11 protons and 7 neutrons. What is the mass number of this isotope?
18
Which substance is important in making plastics?
nitric acid
a person rides a bike with a constant velocity if 2 m/s. if his total displacement is 10 m, for how long was he riding
5 seconds
Substances A and B react in a ratio of A + B → AB. Colin was combining substance A and substance B to form substance AB. He added 10 g of substance A and 45 g of substance B.
55 g
For which pair of objects would adding the same amount of electrons to each object result in a decrease in the electric force?
A. two positively charged objects
A circuit with which components has a current with the greatest voltage?
A. wires, a 9V battery, no resistors
When a spring is compressed, the energy changes from kinetic to potential. Which best describes what is causing this change?
A. work
BELOW THIS IS WRONG ANSWERS
BELOW THIS IS WRONG ANSWERS
Why is scientific notation used?
to express very large or very small numbers
Brain-powered cars may most likely reduce caused by distracted drivers.
traffic accidents
The inertia of two objects Must be the same if the product of their mass and velocity are the same.
true
Fifteen grams of a liquid plastic are frozen in a physical change that increases the volume. What can be known about the plastic after the change?
It will still weigh 15 grams.
A compound that releases hydroxide ions in solution would most likely have which chemical property?
It would react with lipids to form soap.
Denise is riding her bike and falls to the ground. During the collision, she hits both grass and cement.
The grass extends the time of the collision.
What does it mean if an experiment exhibits reproducibility?
The same results are expected each time the experiment is done.
Accuracy
The state of being correct
Andre is predicting the products of chemical reactions. In one reaction, a hydrocarbon is the only reactant. What is the best prediction and explanation of this reaction?
Two new compounds form as the hydrocarbon undergoes a synthesis reaction.
Rudri studies for her physical science test on the history of the atomic model. She creates a table to show how the atomic model has changed over time. Which represents the correct order of development for the atomic model?
X→Y→W→Z
The chart shows the amount of solute that fully dissolved when added to 500 ml of water. Which ranks the solutions in order of greatest to least solubility?
Y → X → Z
If you increase time
You decrease force Vice versa Ft=m*change v
Four canisters contain helium gas. If all the canisters had the same amount of particles, which canister would have the fastest moving particles?
Z
A synthesis reaction will always produce:
a more complex substance
Who would most likely be required to work with sodium hydroxide?
a plumber
The equation shows a neutralization reaction. H2SO4 + 2NaOH Na2SO4 + 2H2O What is Na2SO4?
a salt
What does a triple-beam balance require the user to do?
add the numbers from the three sliders to determine the mass of an object
Which procedure would best allow a scientist to observe a chemical property of hydrochloric acid (HCl) solution?
adding zinc to the HCl solution and observing whether or not bubbles are produced
Alcohol is poured into a beaker that contains 2% saltwater. Which are the solutes in the new solution?
alcohol and salt
The atoms of which elements are most likely to share many electrons among many atoms? Check all that apply.
aluminum (Al) sodium (Na) silver (Ag)
Based on the information in the table, which two elements are most likely in the same group, and why?
bismuth and nitrogen, because they have the same number of valence electrons
The list shows the results of six athletes competing in the long jump, which has a target distance of 20 feet. 12 feet, 11 feet, 13 feet, 10 feet, 20 feet, 12 feet Which best describes the results?
fairly precise but not accurate
Which change will always result in an increase in the gravitational force between two objects?
increasing the masses of the objects and decreasing the distance between the objects
air bags reduce injury in automobile accidents by
increasing time of collision
A product that is a chemically bonded combination of reactants will form in which type of reaction? Check all that apply.
synthesis polymerization oxidation
Which equations can be used to solve for acceleration? Check all that apply.
t = V/a vi = vf - at vf = at + vi a= v/t
Lien made this table to organize her notes on the properties of acids and bases. Which property is in the wrong column?
tastes bitter
Advancements in which field have increased the ability to store increasing amounts of data on electronic devices?
technology
Which factor influences both solubility and the rate of dissolution?
temperature
Marinades for meat commonly include acids such as vinegar or wine, because the acids can
tenderize meat.
Engineers are trying to improve a race car. Their goal is to increase the acceleration of the car using the same engine. Which change shows the best application of Newton's laws of motion to achieve this goal?
decreasing the mass of the car
Which mixture can be separated based on differences in particle size of the components? Check all that apply.
-cereal and milk -smoky air
Which best explains parallel forces? Check all that apply.
-left and right forces that can be added together -upward and downward forces that can be added together
Which method would be best to separate a mixture of iron and lead pellets (of the same approximate diameter)?
-magnetism
Which change will cause the gravitational force between a baseball and a soccer ball to increase? Check all that apply.
-moving the balls closer together -pumping more air into the soccer ball -putting the baseball in a plastic case
How many atoms of each element are in the chemical formula P2O5?
2 phosphorus and 5 oxygen
it takes a runner 2 seconds to accelerate to a speed of 5 m/s near the finish line of a race. if his acceleration is 1 m/s^2, what was his initial velocity
3 m/s
Holden is trying to determine the velocity of his race car. He went 20 meters east, turned around, and went 40 meters west. He turned the car one more time and went 35 meters east. His car was 15 meters from the starting line. This took 5 seconds. What is the car's velocity?
3 m/s east
toby glances at the speedometer on his bike as he begins to roll downhill. it indicates he is traveling at 12 mph when he initially looks at it and 20 miles per hour 4 seconds later. what is his acceleration?
3 mph/s
what is the acceleration of a 1,200kg car when a force of 4,200 N is applied?
3.5m/s^2
"forces occur in pairs" is another way of stating Newtons:
3rd law of motion
Kiley went 5.7 km/h north and then went 5.8 km/h west. From start to finish, she went 8.1 km/h northwest. Which best describes her numbers?
5.7 km/h north and 5.8 km/h west are instantaneous velocities, while 8.1 km/h northwest is the average velocity.
The value of x in the diagram is __°.
50
Which shows the pieces after the magnet is cut?
A.
Olivia places her pet frog on a line to observe the frog's motion. The line is divided into sections that measure 1 centimeter each. The frog begins at 0, moves 18 centimeters forward, moves 6 centimeters backward, and then 12 centimeters backward. What is the frog's displacement?
A. 0
How does an object become negatively charged?
A. It gains electrons.
Mr. Smith is designing a race where velocity will be measured. Which course would allow velocity to accurately get a winner?
A. a 5 mile course from the center of town heading north to the outskirts of town
Apple juice has a lower pH than black coffee. Which best explains the relationship?
Apple juice has more hydrogen ions than black coffee.
How is energy related to the change of state represented by the model?
Atoms gain energy as a liquid changes to a gas.
How is energy related to the change of state represented by the model?
Atoms gain energy as a solid changes to a liquid.
Which statement best describes what happens during a chemical change?
Both the identity and the properties of a substance change.
How is the magnitude of the average acceleration calculated?
By dividing the total change in objects velocity by the time interval in which the change occurs
PLUM PUDDING OR RAISIN MUFFIN MODEL
JJ Thomson
Lithium (Li) has a charge of +1, and oxygen (O) has a charge of -2. Which is the chemical formula?
Li2O
Which statements describe characteristics of all liquids? Check all that apply.
Liquids have molecules that slip past each other. Liquids have definite volume. Liquids flow, even with some resistance. Liquids have the ability to change shape.
If atoms _ energy during a change of state, they are pulled together by attractive forces and become more organized.
Lose
Atoms of iron (Fe) form metallic bonds with other iron atoms. How are the valence electrons of these atoms rearranged to form the bonds?
Many valence electrons are shared between the atoms
Terminal Speed
Maximum speed an object can go in free fall
The square root of the final velocity may be what?
May be positive or negative, based on direction.
Two models of the same compound are shown. In what way is Model B better than Model A?
Model B shows how the atoms in the molecule are connected, but Model A does not.
The law of conservation of momentum states that, if left alone, the total momentum of two interacting objects that make up a system .
Remains the same
Group 1; alkali metals
What group are said to be extremely reactive?
The object has mass, but it does not have any "mass in motion"
Why is the momentum of an object at rest equal to zero?
Describe at what point velocity would be zero if you tossed a ball up in the air.
at the peak of the parabola
If the number of atoms in the reactants equals the number of atoms in the products, the equation is
balanced
Thomson
developed the first model of the atom that showed the structure of the inside of an atom.
While looking at calcium (Ca) on the periodic table, a student needs to find an element with a greater atomic mass in the same period. Where should the student look?
directly to the right
The number at the end of an isotope's name is the -mass number. While looking at xenon (Xe) on the periodic table, a student needs to find an element with a smaller atomic mass in the same group. Where should the student look?
directly up
While looking at xenon (Xe) on the periodic table, a student needs to find an element with a smaller atomic mass in the same group. Where should the student look?
directly up
You are walking on a track. You move 40cm away from your origin, then turn around and come 20 cm back. What is your displacement, and your distance?
displacement=20cm distance 60cm
Reproducibility is the ability of data to be
duplicated
is two billiards colliding and bouncing off eachother inelastic or elastic?
elastic
An electric generator converts kinetic energy into _____ energy.
electrical
The part of an atom that is mostly empty space is the
electron cloud
Evaporation is a process that requires energy to occur. Evaporation is a(n)____ reaction.
endothermic
the ability to cause change is defined as
energy and is measured in joules
What did Bohr's model of the atom include that Rutherford's model did not have?
energy levels
Helen needs to make a supersaturated solution of saltwater. Which describes the best way to make the solution?
increase the temperature of the solution and add more salt
Which statement best describes a human influence on the biogeochemical cycles?
increased eutrophication caused by high levels of nitrogen and phosphorous
Which most likely represents the process of dissolving carbon dioxide in soda?
increased pressure to increase solubility
An advertisement for a new fish food claims that lab studies show that fish grew three inches in three weeks while eating the food. Travis wondered if the food was worth the extra cost. To evaluate the claim in the advertisement, Travis should
look at the data for the control group to see how much the fish grew without the new food.
Which equation is most likely used to determine the acceleration from a velocity vs. time graph?
m = y2-y1 / x2-x1
Eugene describes the physical property of a material as "sweet and floral." What physical property of the material is Eugene most likely observing?
odor
When converting a number from scientific notation to standard notation, if the power of 10 is
positive, move the decimal point to the right.
View the spinner. http://media.edgenuity.com/evresources/3208/3208-01/3208-01-07/3208-01-07-assessment/3208-01-07-24.png In which area is it impossible to land?
purple
Scientists in a particular field strive for the same quality of work because they know their peers will be reviewing their scientific claims. What does this review process help ensure?
standards of the profession
Which example would most likely decrease friction?
using shaving cream, rather than shaving on dry skin
What is the acceleration of a 1,600 kg car when a force of 5,200 N is applied?
x=3.25m/s2
According to Newton's first law, which characteristic of a moving object would remain constant if there were no other forces acting on it?
Speed
Which statement explains how gravity and inertia work together?
They change the motion of objects.
Which best describes the purpose of bar graphs?
They compare quantities for particular categories.
Action and reaction forces are described by Newton's_____law of motion.
Third
A 3 kg piece of clay moving at 5 m/s strikes and sticks to a second 5 kg piece of clay moving at 2 m/s. Calculate the speed of the combined piece of clay. (Find V 3 )
V3=3.13 m/s
Calculate the speed of your cat chasing a mouse 200 yards in 15 seconds
V= 13.3 yards/sec
Which statement best describes the diagram below?
A. The pressure is greater at the bottom of the container.
Which energy transformation does the picture best illustrate?
A. radiant to chemical
Which best describes the pH scale?
Acids measure below 7.
The force your bumper car exerts on the other car is the action force. The force the other car exerts on your car is the reaction force. These two forces are equal in size and opposite in direction. Other examples: Pressing your hand against a wall and a hammer and a nail
Action and Reaction Forces
Jamal was riding his bike home at a speed of 12 mph. On his trip out, he had traveled 8 miles away from his house. He has been traveling for a half hour at this speed. How far away from home is he?
B. 2 miles
What is produced during the replacement reaction of Ba(NO3)2 and Na2SO4?
B. 2NaNO3 + BaSO4
A cart accelerates at 2 m/s2 when a force of 60 N is applied. What is the mass of the cart? (Formula: F=ma)
B. 30 kg
Which is a valid velocity reading for an object?
B. 45 m/s north
If the change in velocity increases, what happens to the acceleration during the same time period?
B. Acceleration increases.
Which statement is best supported by the information in the chart?
B. Wave X and Wave Y are electromagnetic waves, and Wave Z is a mechanical wave.
Which headings best complete the chart?
B. X: Opaque Objects Y: Transparent Objects
What are the products of the combustion of a hydrocarbon?
B. carbon dioxide and water
Chalk is an ionic compound. Which is a property of all ionic compounds that makes chalk particularly useful for writing on a chalkboard?
B. hardness and brittleness
Jerome solves a problem using the law of conservation of momentum. What should Jerome always keep constant for each object after the objects collide and bounce apart?
B. mass
An object that is made of which material is likely to be attracted to a magnet?
B. nickel
Manny walked a total of 3 miles. The reference point used to calculate the total distance that he walked was the same as the ending point. Which describes where Manny most likely walked?
B. on a circular nature trail
What is the function of the slip rings in an electric generator?
C. producing a path for current to flow
Lin Yao looks at the back of a spoon. How should she describe her reflection?
C. right-side up and smaller
The element carbon (C) is most likely to form covalent bonds with the element
C. selenium (Se).
Which imaging technique uses sound waves rather than electromagnetic waves?
C. sonography
There are several ways to model a compound. One type of model is shown. What is the chemical formula for the molecule modeled?
C6H12O2
Which is an example of a polyatomic ion?
CO3-
Marco is conducting an experiment. He knows the wave that he is working with has a wavelength of 32.4 cm. If he measures the frequency as 3 hertz, which statement about the wave is accurate?
D
The graph below shows a velocity vs. time graph. Which graph would match the same type of movement that the graph shows?
D
Impact force
Force that causes impulse
How should the resistance change to return the current to its original value if the voltage remains at its increased amount?
NOT B, C
Which best explains how to correct Alana's error?
NOT B, C
What is produced during the replacement reaction of Cu(NO3)2 and Zn?
Zn(NO3)2 + Cu
Which actions are evidence that a chemical reaction has occurred? Check all that apply.
a change in color the formation of a precipitate a clear liquid becoming cloudy the formation of bubbles the formation of smoke
Nio conducts a science experiment. He puts yeast into a bottle with water and sugar, and then caps the bottle with a balloon. He returns two hours later and notices there are bubbles on the surface of the mixture in the bottle and that the balloon has inflated, but there are no other apparent changes. What most likely happened?
a chemical change, because a gas was produced
when two objects hit each other what occurs?
a collision
Which professional most likely uses X-ray technology? Check all that apply.
a dentist an astronomer an airport-security screener
Which jar contains a mixture?
a jar of copper and water
A solution has a pH of 2. Which best describes the solution?
a strong acid
Which of the following is a basic solution?
a. household ammonia
the rate of change in the speed of an object is known as
acceleration
The minimum amount of energy required to start a chemical reaction is the _________ energy.
activation
In a single replacement reaction, hydrogen gas can be produced when a(n) ______________________ replaces H from water or acid
active metal
When dissolved in water, all acids will
conduct electricity.
Which describes the best approach when conducting a scientific experiment?
conduct repeated trials and make sure the experiment can be replicated
Which balances the equation Mg + O2→ MgO?
2Mg + O2 → 2MgO
What is produced during the replacement reaction of Ba(NO3)2 and Na2SO4?
2NaNO3 + BaSO4
An acid or a base dissolved in water breaks down into a positive and a _____ ion.
negative
A local meteorologist reports the day's weather. "Currently sunny outside, 34°F. Skies will become overcast later this afternoon, as temperatures drop to 25°F, with windy conditions out of the north at 10-15 miles per hour. Radar indicates 2-3 inches of snow expected to fall later tonight." Which information is qualitative? Check all that apply.
"sunny" "overcast"
You raise one penny per meter walked in a fundraiser. You walk 11 km. How many dollars do you raise?
$110
They also knew that the electron had little orno mass, therefore he reasoned that all of an atom's mass is in positively charged nucleus. He called these positively charged particles in the nucleus, protons.
(Earnest Rutherford)
What value is closest to the mass of the atom?
10 amu
Ana exerts a force of 20 N on a volleyball that has a mass of 0.15 kg. What is the force that the volleyball exerts on Ana?
20 N
An atom of the element chromium has an atomic number of 24 and a mass number of 52. How many electrons are in an uncharged atom of chromium?
24
If carbon monoxide reaches a temperature of over 1,100 degrees Fahrenheit, it will ignite in a combustion reaction with oxygen. What would the product(s) of the reaction be? 2CO + O2 → ?
2CO2
Which additional product balances the reaction H2SO4 + 2NaOH → Na2SO4 + ________?
2H2O
What are the products of the neutralization reaction of NaOH with HNO₃? (Do not include spectator ions.)
2H₂O
What are the products of the neutralization reaction of KOH with HCl?
2H₂O + K⁺ + Cl⁻
In the reaction C + O2 → CO2, 18 g of carbon react with oxygen to produce 72 g of carbon dioxide. What mass of oxygen would be needed in the reaction?
54 g
The graph is the path Beth took on a walk. What does the line from time 6 to 10 indicate?
Beth went back toward her origin.
Impulse
Change in momentum
Letti is having a problem in her experiment that she does not know how to solve. In order to move forward, Letti needs to be
Creative
Which separation procedure is most likely to happen?
Filtering a mixture will separate it into substances.
Which notations are commonly used on force diagrams to show forces acting on an object? Check all that apply.
Fp FN Ff Fg
The impulse necessary to change the momentum of a 25 kg object by 3 kg*m/s is how much?
Ft= 75 N.S
The descriptions below explain two ways that water is used by plants on a sunny day. I. In a process called transpiration, some liquid water in leaves changes to water vapor. The water vapor is released into the air through tiny pores in the leaves. This allows more liquid water from the soil to be pulled up the roots and stem to replace water lost from the leaves. II. Plants use some of this water in leaves in a process called photosynthesis. During photosynthesis, water and carbon dioxide break apart and recombine to form two new substances, oxygen and glucose. Based on the above description of transpiration and photosynthesis, which type of change happens to water during each process?
In transpiration, because some of its properties change, water undergoes a physical change but keeps its identity. In photosynthesis, because its identity changes, water undergoes a chemical change.
Two objects sticking to each other.
Inelastic Collision
Which property describes a mixture? Check all that apply.
It can be separated by physical methods. It can appear different from different sources. It cannot be described by a chemical symbol or formula.
Which property describes a mixture? Check all that apply.
It can be separated by physical methods. It can appear different from different sources. It cannot be described by a chemical symbol or formula.
Which best describes a mixture?
It can have different compositions, and it has a set of characteristics that does change.
The _____ force is the sum of all the forces that act upon an object.
NET
What property allows salt to be collected from ocean water?
Salt has a higher boiling point than water.
If 2 objects have the same momentum, then
The heavier object will travel slower
S.I. System
The international set of units
A lunar vehicle is tested on Earth at a speed of 10 km/hr, driving at the same speed on the moon
The momentum is the same
What did Rutherford's model of the atom include that Thomson's model did not have?
a nucleus
Which does a reference point provide? Check all that apply.
a position from which to measure future distance a way to detect an object's motion
The equation shows a neutralization reaction. H2SO4 + 2NaOH Na2SO4 + 2H2O What is Na2SO4?
a salt
Glen rolls down a hill on his bike. He was going 12 mph at first, then was going 18 mph at the bottom 4 seconds later. What was his acceleration?
a= 1.5 mph/sec
Which means "to study or examine"?
analyze
A force that holds atoms together is a chemical
bond
A scientist conducted one trial of an experiment and got unexpected results. How can the scientist increase confidence in the results?
by repeating the experiment several times
What does the pH of a solution measure?
concentration of H₃O⁺ ions
During which method of separation is one of the components of the mixture lost?
evaporation
Balanced chemical equations express the law of conservation of
mass
A chemical reaction that has the general formula of AB + C → CB + A is best classified as a__________ reaction.
single displacement
potential energy increases as
slows rolling up an incline
A student uses red litmus paper to test the pH value of different solutions. Which would result in a color change of the litmus paper?
soap drain cleaner
A substance with a definite shape and volume is a _______ phase of matter.
solid
How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players can pass a puck as quickly as possible?
Smooth ice reduces the unbalanced forces that would slow the hockey puck.
Prior to the invention of a revolutionary means of travel, people had to take long, dangerous journeys to cross parts of the country. Due to this development, society was revolutionized as travel became safe and efficient.
Steam
Which compounds are used in batteries? Check all that apply
Sulfuric Acid Pottassium Hydroxide
Theorized that electrons must have only a specific amount of energy. This is similar to the way planets move around the sun.
(Neils Bohr)
a car brakes suddenly and the velocity changes from 25 m/s to 0 in 5 seconds. what is its acceleration?
-5m/s
What happens during evaporation?
A liquid changes to a gas.
Which best describes the runners?
A. Daniela had a 5 meter head start, and Leonard caught up to her at 25 meters.
Lila is a track and field athlete. She has to complete four laps around the track, which is 400 meters. The race took her 6 minutes to complete. Which best describes her speed and velocity?
A. Her speed is 4.4 m/s, and her velocity is 0 m/s.
Which units are used to measure force?
A. newtons
Which best describes a chemical reaction?
A. the rearrangement of atoms by breaking and reforming chemical bonds
Roshan describes the basic parts of an electric circuit using a shower as a model. Which part of a circuit does the water pipe represent?
A. the wire
Displacement depends on what?
Acceleration, initial velocity and time.
When delta V is positive what else is positive?
Acceleration, vice versa.
Impulse
Amount of force over time, a force acting over a period of time
Which is an unreliable source?
An advertisement for acne medication claims it can clear up acne in less than one week.
What does the octet rule state that explains why atoms bond?
An atom bonds to have eight valence electrons to become stable.
What new characteristic did John Dalton add to the model of the atom?
An atom can join with other kinds of atoms.
the charged particles in the beams that Thomson studied came from atoms. As these particles moved away from their original atoms, they formed a visible beam. The current model of the atom includes protons, neutrons, and electrons. What is the best use of an atomic model to explain the charge of the particles in Thomson's beams?
An atom's smaller negative particles are at a distance from the central positive particles, so the negative particles are easier to remove.
Which argument best explains the charge of an atomic nucleus?
An atomic nucleus is positively charged because it is composed of protons.
Which label belongs in the area marked X?
B. Magnetic field
Which describes an image that a concave mirror can make?
B. The image can be either virtual or real.
Which is an example of a chemical reaction?
B. paper burned and turned into smoke
Which lists types of materials from most conductive to least conductive?
B. superconductor, conductor, semiconductor, insulator
Which simple machine is best used to split apart an object?
C. a wedge
If two substances combine to form a new substance with different properties, a ________ change has occurred.
Chemical
How does using a ramp make work easier when loading a piano onto a truck three feet above the ground?
D. It allows a smaller force to be applied over a longer distance.
Which best describes a mixture?
D. It can have different compositions, and it has a set of characteristics that does change.
Investigations were carried out in a science lab to explore the topic of chemical and physical changes. Investigation A Step 1. Add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible. Step 2. Heat the salt solution on a burner until only a white solid remains. Investigation B Step 1. Mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible. Step 2. Heat the sugar solution on a burner until the solution thickens and turns brown. Which step did a chemical change most likely occur?
Investigation B, Step 2 only
The amount of matter in an object; SI unit for measuring mass is the kilogram.
Mass
Mass in motion; a measure of how hard it is to stop the object (p = m*v ---- kg x m/s).
Momentum
More momentum equals
More mass or more velocity or both
In which areas of the diagram does conduction occur?
NOT A, D
At which position would the electric force be greatest?
NOT A,B
What is the wavelength of this wave?
NOT A. 1
How does a foam-filled winter coat help keep a person warm?
NOT A. It slows down the transfer of thermal energy from outside to inside the coat.
When all else remains the same, what effect would decreasing the focal length have on a convex lens?
NOT A. It would cause the lens to produce only real images.
What happens when heat is removed from water?
NOT A. The water particles move farther apart.
This is an example of using a hammer as a(n)
NOT B. pulley.
What is occurring when a light wave goes through a pane of glass in a window?
NOT C. constructive interference
Which most likely has the greatest conductivity?
NOT D, A
Which describes an image that can be produced by a concave lens?
NOT D. The image is real and larger than the object.
How does an increase in thermal energy affect molecules?
NOT D. They lose kinetic energy.
What is the correct classification of a mixture in which both a solid and a liquid are visible?
NOT a homogeneous mixture and a solution
Is the sum of all forces acting on an object. It is capable of accelerating a mass. For instance, if the wheels of a car push it forward with 5 Newtons and drag is 3 Newtons , the net force is 2 Newtons, forward. Like vectors, you can combine force arrows to show the result of how forces combine. Forces in the same direction add together and forces in opposite directions subtract from one another
Net force
A force cannot exist alone. Forces always exist in pairs. According to Newton's third law of motion, whenever one object exerts a force on a second object, the second object exerts an equal and opposite force on the first object
Newton's Third Law
________ acceleration occurs when an object speeds up.
Positive
What is the main difference between protons and neutrons?
Protons have an electrical charge, but neutrons have no charge.
Displacement
The moving of something from its place
Precision
The quality
Schroedinger
Theorized that electrons move in orbitals (energy levels) around the nucleus but NOT in a set path (Wave Model)
(Nagaoka)
Theorized the Saturnian MOdel which a large center nucleus with electrons orbiting the nucleus
Which statement best describes the atoms in a gas
They move freely in all directions.
Davahl is interested in tortoises because they can live for over a hundred years and have unique metabolisms. She wants to perform an experiment to see if they can live even longer with a specific nutrient supplement. Davahl is given a five-year research grant to perform her experiment.
Time
According to Newton's third of motion, whenever an object exerts a force on a second object, the second object exerts an equal and opposite force on the other object. These two forces are called the action and reaction forces.
Using Newton's Third Law, explain what is meant by action and reaction pairs of forces
When work is measured in joules and time is measured in seconds, power is measured in _____.
WATTS
A force acts on an object and moves it a certain distance. The product of the force and the distance is the _____ done on the object
WORK
Which statement explains how weight is different from mass?
Weight is a measure of gravitational pull.
the number of shells it possesses
What do the horizontal rows on the periodic table indicate about the element?
rows
What do we call the horizontal rows on the periodic table?
Groups
What do we call the vertical columns on the periodic table?
Boron
What element has 3ve and 2 shells?
Sari is studying four different samples of materials. This table shows the mass and volume of the samples. Which sample material(s) could be liquid?
X
There are several different models that represent compounds. One type of model is shown. What type of model is shown?
a structural formula
Which scientific tool helps to make distant objects appear nearer and larger?
a telescope
Which is a valid ionic compound?
a valid ionic compoun
A solution has a pH of 8. Which best describes the solution?
a weak base
Which solution is the most acidic?
a. apple juice, pH = 3
A roller coaster traveling at 8 m/s speeds up to 12 m/s in 3 seconds as it goes down a hill. What is the acceleration?
a= 1.3 m/s2
A synthesis reaction will produce a single _____
compound
Newton's Second Law of Motion
force is mass times distance
Which type of replacement reaction is NaCl (aq) + AgNO3 (aq)→ NaNO3 (aq) + AgCl (s)?
formation of a precipitate from solution
Which describe colloids? Check all that apply.
heterogeneous mixtures. may have a uniform appearance, are made up of at least two substances.
what is not an important part of studying physics?
memorizing complicated explanations
if an object is accelerated, what WONT it do?
remain motionless
Atoms in a _______ stay in a fixed position and have no freedom to move.
solid
Haley is trying to pull an object upward. The below forces are acting on the object. Fp = 5500N Fg = 6000N Which represents the net force?
↓ 500N
The mechanical advantage of the lever is
2
The amount of oxygen in the reactants is 4 atoms. In the products, the oxygen is distributed to water (H2O) and O2 gas. Which coefficients would be placed in front of water and oxygen?
2 in front of water and 1 in front of oxygen
The chart shows Daniela's run through her race. What is her velocity?
2.5 m/s
All atoms of the element potassium have 19 protons. One of the most stable types of potassium atoms has the mass number 39. How many neutrons make up one of these potassium atoms?
20
what net force is required to accelerate a 10 kg wagon by 2 m/s^2
20 N
Which balances the equation Mg + O2 → MgO?
2Mg + O2 → 2MgO
A cart accelerates at 2 m/s2 when a force of 60 N is applied. What is the mass of the cart? (Formula: F=ma)
30 kg
the speed of a cheetah running 300 yards in 10s is
30 yards per second
This is how krypton appears in the periodic table. Rounded to the nearest whole number, how many protons are in an atom of krypton?
36
a ball is dropped off the roof of a tall building. if the ball reaches the ground in 3 seconds. what is the average speed?
44.1 meters
Rolf is comparing four solutions. Solution A was placed in the fridge, which is at 4°C. Solution B was placed at room temperature, which is 20°C. Solution C was placed in an incubator at 37°C, and solution D was boiled at 100°C. Rolf then added the same amount of solute into each solution and agitated it at the same speed. The chart indicates his results for the amount of solute dissolved.
4°C
Rolf is comparing four solutions. Solution A was placed in the fridge, which is at 4°C. Solution B was placed at room temperature, which is 20°C. Solution C was placed in an incubator at 37°C, and solution D was boiled at 100°C. Rolf then added the same amount of solute into each solution and agitated it at the same speed. The chart indicates his results for the amount of solute dissolved. Which temperature allowed for an unsaturated solution?
4°C
the impulse necessary to change the momentum of a 20 kg object by 5 kg*m/s is
5 kg*m/s
Substances A and B react in a ratio of A + B → AB. Colin was combining substance A and substance B to form substance AB. He added 10 g of substance A and 45 g of substance B. How much of substance AB would Colin make?
55 g
Sayid made a chart listing data of two colliding objects. According to the law of conservation of momentum, what is the missing value in the chart?
6
Sayid made a chart listing data of two colliding objects. According to the law of conservation of momentum, what is the missing value in the chart?
6
A car is traveling in a race. The car went from the initial velocity of 35 m/s to the final velocity of 65 m/s in 5 seconds. What is the acceleration?
6 m/s2
________ is a process that involves the collection of information and ideas supported by belief or opinion.
??
Explains whether Bromine (BR) or Neon (NE) is more likely to form a covalent bond?
A
In a science lab, Cash mixes two clear liquids together in a beaker. Bubbles are produced, and a white solid forms and settles to the bottom. He plans to heat the beaker over low heat and make more observations.
A chemical change occurred, so even if Cash heats it, the white solid will remain.
In a science lab, Cash mixes two clear liquids together in a beaker. Bubbles are produced, and a white solid forms and settles to the bottom. He plans to heat the beaker over low heat and make more observations. Which statement is most likely correct?
A chemical change occurred, so even if Cash heats it, the white solid will remain.
Which statement correctly describes whether a compound is a pure substance?
A compound is a pure substance because its molecule cannot be broken down into simpler particles by physical means.
Which statement correctly describes why a compound is a pure substance?
A compound is a pure substance because its molecule cannot be broken down into simpler particles by physical means.
Which reactants can be used to identify a chemical reaction as a combustion reaction?
A hydrocarbon reacts with oxygen.
As atoms gain energy, they move faster and slide past one another more easily. Atoms at the surface of the substance overcome attractions to nearby atoms and break free of the surface.
A liquid to Gas
Andre is predicting the products of chemical reactions. In one reaction, a hydrocarbon is the only reactant. What is the best prediction and explanation of this reaction?
A polymer forms because the hydrocarbon joins with itself in a polymerization reaction.
An analogy makes a comparison between objects based on their similar qualities. Cassidy wanted to create an analogy for the motion of atoms in solids, liquids, and gases, so she compared them to marbles in a tray. Which best compares the phases of matter to marbles in a tray?
A solid is like the tray being shaken slowly and all the marbles moving in their positions, a liquid is like the tray being shaken and the marbles moving around it, and a gas is like the tray being shaken hard and the marbles moving vigorously around it.
Polly is pushing a box across the floor with a force of 30 N. The force of gravity is -8 N, and the normal force is 8 N. Which value could describe the force of friction if Polly could not move the box?
A. -30 N
Jill applies a force of 250 N to a machine. The machine applies a force of 25 N to an object. What is the mechanical advantage of the machine?
A. 0.1
The activation energy of a reaction going on its own is 20 kJ. If the reaction was treated with a catalyst, which would most likely represent the amount of energy needed to start a reaction?
A. 15 kJ
How many atoms of nitrogen are in the chemical formula Ni(NO3)2?
A. 2
What is the mass of a crate if a force of 200 N causes it to accelerate at 8 m/s2? (Formula: F=ma)
A. 25 kg
Rosa was looking for patterns to help predict the products of chemical reactions. She recorded three similar decomposition reactions in the table. What products should she record in the last row of the table?
A. 2LiCl + 3O2
One half of a balanced chemical equation is shown. 3Mg(OH)2 + 2H3PO4 Which lists the numbers of each atom the other half of the equation would contain?
A. 3 Mg, 2 P, 14 O, 12 H
A ball has a mass of 140 g. What is the force needed to accelerate the ball at 25 m/s2? (Formula: F=ma)
A. 3.5 N
Theresa creates an experiment where she mixes two red-colored substances together in a container and observes the solution slowly changing from red to blue for the next eight minutes. The solution becomes completely blue after eight minutes. What does this represent about the type of change happening in the container?
A. A chemical change started immediately and finished at eight minutes.
Which is a characteristic of all waves?
A. All waves carry energy.
Three students are working with different substances to measure the chemical changes that occur. Chao is working with milk, Mia is working with carbon dioxide gas, and Ezra is working with rock. Which would best describe the way to treat each substance to get a faster reaction?
A. Chao should change the temperature, Mia should adjust the pressure, and Ezra should increase the surface area.
Which statements describe a closed circuit? Check all that apply.
A. D. E.
Why can a hydrogen atom form a covalent bond without fulfilling the octet rule?
A. Hydrogen's valence shell can hold only up to two electrons.
While researching machines and how they work, Tika finds several online sites that discuss how force and distance are related to work done by a machine. How should Tika most likely describe this relationship between force and distance to her study group?
A. If the input force is less than the output force, then the input distance must be greater than the output distance.
Olaf takes a picture of his dog using a digital camera. Which is true regarding the image of the dog detected by sensors in the camera?
A. It forms where light rays coming from the dog converge.
Which best describes what happens when light traveling through air enters water at an angle?
A. It moves along straight lines in air and changes direction when it enters water.
Which conclusion is supported by this evidence?
A. Neither ball has a charge.
Why is reaching activation energy necessary?
A. Reactants require a minimum amount of energy to start to break a chemical bond.
Elena makes the table below to determine the number of atoms of each element in the chemical formula 3(NH4)2SO4. What mistake did Elena make?
A. She should not have multiplied the sulfur atoms by the subscript 4.
What will most likely occur if sulfur forms an ionic bond with another element?
A. Sulfur will accept electrons.
Which best explains why the bell would not ring in this set-up?
A. The circuit is open.
When the resistance in a circuit remains constant, how are the voltage and current related?
A. The current doubles when the voltage doubles because they are directly proportional.
Jasper and Gemma are going to play on a teeter totter. Gemma gets on first. When Jasper gets on, Gemma moves into the air, but she does not move to the top. Which statement could correctly explain the forces acting on the teeter totter?
A. The forces are balanced because Jasper weighs the same as Gemma.
Which best explains what happens to the motion of the pendulum?
A. The mechanical energy transforms to thermal energy as the pendulum slows and eventually stops moving.
What information on the periodic table is used to complete electron dot diagrams?
A. The number before the A at the top of a column shows how many dots to draw in the diagram.
Why is the choice of a radiopharmaceutical important in radioisotope imaging?
A. The radiopharmaceutical must localize to the specific organ or tissue to be imaged.
Which clue can be used to identify a chemical reaction as a replacement reaction?
A. The reaction has two reactants with ions that seem to switch places.
Which statement best describes the skier?
A. The skier has potential and kinetic energy.
Keisha is making a diagram of a simple machine in the body. Which labels complete the diagram?
A. X: load Y: fulcrum Z: lever
Mr. Smith is designing a race where velocity will be measured. Which course would allow velocity to accurately get a winner?
A. a 5 mile course from the center of town heading north to the outskirts of town
Enzymes are added to a chemical reaction to lower the activation energy. What is an enzyme classified as?
A. a catalyst
Which most likely describes a supersaturated solution?
A. a hot solution with all of the solute dissolved
Which most likely indicates a chemical change has occurred?
A. a solid substance becoming larger
Which example best represents balanced forces?
A. an elevator stopped on the third floor
What is the most likely way in which an atom of magnesium (Mg) will satisfy the octet rule when it forms bonds?
A. by losing two electrons
Which is an example of a chemical change?
A. frying an egg
Which is a property of laser light that makes it useful for cutting metals?
A. its focused energy
Barbara is converting 78°F to degrees Celsius. First, she subtracts 32 from 78. What is the next step?
A. multiply 46 by 5/9
Covalent bonds can be best described as...
A. neutral atoms coming together to share electrons.
Energy can be transformed from one form to another. The diagram shows one such process. Which energy transformation is represented in the diagram?
A. nuclear to thermal and radiant
Diego is trying to lift a piano to the second floor of his house. Diego uses a pulley system and gives a big lift to the piano.The piano moves upward, then stops, and then it starts to fall to the ground. Which list best describes the forces on the piano in the proper order?
A. positive force → balanced force → negative force
When sodium atoms (Na) and chlorine atoms (Cl) join to make sodium chloride, or table salt, they form an ionic bond. Using this information, which pair of elements is most likely to form an ionic bond?
A. potassium (K) and fluorine (F)
Which behavior is the spoon in the top image most likely being used to illustrate?
A. refraction
When Coach Kwan notices that a player is getting tired, she takes out the tired player and substitutes a fresh player. Which type of chemical reaction does this best model?
A. replacement
What would decrease the resistance of wires carrying an electric current?
A. shorter wires
Which symbol and unit of measurement are used for resistance?
A. symbol: R; unit Ω:
When someone throws a ball, the action force is the person pushing on the ball. What is the reaction force?
A. the ball pushing on the person
What do the arrows represent?
A. the magnetic field
The chart shows the movement of a ball after several seconds. Column A is on the x-axis, and Column B is on the y-axis. Which titles should replace A and B?
A. Column A should be "Time," and Column B should be "Position."
Lila is a track and field athlete. She has to complete four laps around the track, which is 400 meters. The race took her 6 minutes to complete. Which best describes her speed and velocity?
A. Her speed is 4.4 m/s, and her velocity is 0 m/s.
Football helmets are made with padding that helps reduce head injuries when a player collides with an object. Which best explains how the padding reduces injuries?
A. It extends the time of the collision.
A student takes notes in class as shown below. A. Uses an objective process Is updated constantly B. Is not objective Does not use a process Resists new information Which are the best titles for A and B?
A: "Science"; B: "Pseudoscience"
Juan inflates a balloon and then releases its end to let the balloon go free as air comes out. The balloon then flies around the room. Which statement describes how this example is an application of Newton's laws of motion?
According to Newton's third law of motion, the balloon is pushed forward as the air is forced out.
What is the difference between accurate data and reproducible data?
Accurate data are close to the correct or accepted value. Reproducible data can be duplicated. Reproducible data are not always accurate.
Why is a protective apron or lab coat important to use when working with acids?
Acids break down fabrics and can cause burns if the acids are strong.
Which procerdure would best allow a scientist to observe a chemical property of hydrochloric acid (HCI) solution?
Adding zinc to the HCI solution and observing whether or not bubbles are produced.
Read the excerpts about climate change. Article 1, found on the website of the Natural Resources Defense Council, a certified charitable organization, supports global warming. Global warming doesn't create hurricanes, but it does make them stronger and more dangerous. Because the ocean is getting warmer, tropical storms can pick up more energy and become more powerful. So global warming could turn, say, a category 3 storm into a much more dangerous category 4 storm. In fact, scientists have found that the destructive potential of hurricanes has greatly increased along with ocean temperature over the past 35 years. Article 2 was written by Michael Fumento, writer for the New York Post editorial blog, who does not support global warming. Back in 2005 I and others reviewed the entire hurricane record, which goes back over a century, and found no increase of any kind. Yes, we sometimes get bad storms—but no frequently now than in the past. The advocates simply ignored that evidence. Fact is, the earth was cooling and warming long before greenhouse gases could have been a factor. The [global warming supporters] have been proved wrong time and time again. Which best justifies the accuracy of the claim?
Although Article 1 mentions evidence discovered by scientists, more research is needed about the data source to determine if the claim is scientific.
Dominic made the table below to organize his notes about mixtures. What mistake did Dominic make?
Although it is possible to have more than one state, it is also possible to have only one state.
Which statement best describes how an existing theory is often affected by the development of new technology?
An existing theory is modified so that it can explain both the old and new observations.
The table shows the relationship between the masses of two objects, the distance between the two objects, and the gravitational force between the objects. Which conclusion is supported by the data in the table?
An increase in the distance between the objects causes a greater change in the gravitational force than the same increase in mass.
Tyler and his family drove from Atlanta to Baltimore. They traveled a total of 678 miles over 2 days. What is the reference point in this scenario?
Atlanta
Which statement best describes the energy changes associated with evaporation and boiling?
Atoms gain energy during evaporation and boiling.
Lexi is balancing equations. She is finding one equation to be very difficult to balance. Which explains how to balance the equation ZnSO4 + Li2CO3 → ZnCO3 + Li2SO4?
Atoms in the equation are already in balance.
Water is made of two hydrogen atoms and one oxygen atom bonded together. Julia is describing how water undergoes a physical change when it boils. She says that the particles shift to be farther apart and that the oxygen and hydrogen separate. She also says that the total mass of the steam is the same as the initial water, and that heat energy was required to cause the change. She finishes her description by saying that the steam can be turned back into water if it is cooled. Which is the mistake in her description?
Atoms remain bonded to each other in physical changes.
What is the relationship between radiopharmaceuticals, tracers, and radionuclides?
B A radionuclide is part of a radiopharmaceutical, which functions as a tracer.
What will occur when the trough of Wave A overlaps the trough of Wave B?
B Constructive interference will occur, causing the new wave to have more energy than Wave A or Wave B.
An object starts at position 12 on a horizontal line with a reference point of 0. What is the position of the object if it moves 14 units to the left?
B. -2
What is the temperature, in degrees Celsius, of a substance with a temperature of 49K?
B. -224°C
An object has a velocity of 8 m/s and a kinetic energy of 480 J. What is the mass of the object?
B. 15 kg
A bowling ball has a mass of 7.2 kg and a weight of 70.6 N. It moves down the bowling alley at 1 m/s and strikes a pin with a force of 15.0 N. What is the force that the pin exerts on the bowling ball?
B. 15.0 N
Which coefficient is needed in front of NaNO3 to balance the equation Na2S + Zn(NO3)2 → ZnS + _NaNO3?
B. 2
Which ray shows the correct direction of the reflected ray?
B. 2
A car is moving at 12 m/s and has a mass of 600 kg. What is the kinetic energy of the car?
B. 43,200 J
Juan inflates a balloon and then releases its end to let the balloon go free as air comes out. The balloon then flies around the room. Which statement describes how this example is an application of Newton's laws of motion?
B. According to Newton's third law of motion, the balloon is pushed forward as the air is forced out.
Which best compares scissors and a seesaw?
B. Both involve the use of levers.
There are several ways to model a compound. One type of model is shown. What is the chemical formula for the molecule represented by the model?
B. C4H9O2
Which best compares AC and DC?
B. DC flows in one direction, and AC repeatedly switches direction.
Which statement best describes echolocation in bats?
B. Echolocation helps bats find food and avoid flying into obstacles.
Which statement best describes echolocation in dolphins?
B. Echolocation helps dolphins find food and avoid predators.
Which best describes Jodi's error?
B. Electrons move from areas of high to low electric potential.
Beverly and Carl are in a race. Their graphs show the data. Which best describes the race?
B. Even though for a majority of the race they accelerated at the same rate, Beverly won because her initial acceleration was greater than Carl's.
Which best describes his run?
B. From time 6 to 10, he was at his slowest.
The chart shows the time, initial velocity, and final velocity of three riders. Which best describes the riders?
B. Gabriella is slowing down at the same rate that Kendall is speeding up, and Franklin is not accelerating.
How can Dante correct the diagram?
B. He can connect the wire to both ends of the ammeter.
For a science fair project about food and chemistry, Bill looks around his kitchen for examples of covalent compounds. What evidence can Bill use in his project to show that water (H2O) acts like other covalent compounds?
B. He can demonstrate that water can be boiled on a simple kitchen stove.
Isla's change in velocity is 30 m/s, and Hazel has the same change in velocity. Which best explains why they would have different accelerations?
B. Isla had a different time than Hazel.
Otis watches a cooking show on making mayonnaise. The chef dissolves salt and sugar in vinegar. She mixes in an egg yolk, and then mixes in oil until the ingredients are completely blended together. The chef says that it's great on sandwiches and that it can be stored without separating. Which best describes the purpose of the egg yolk in the recipe?
B. It acts to hold the vinegar and oil together in a colloid.
Khalad is measuring the amplitude of a wave. What can be known about this wave?
B. It is a transverse wave.
What does the chemical formula CaCl2 show about the compound it represents?
B. It is made up of two elements.
Shareen performs a skit to model a method of charging. In the skit, a painter shakes her hand and gets paint on her. How does the skit model a method of charging?
B. It models conduction because the painter represents a charged object and the paint represents electrons that are transferred through contact.
Alana summarized what happens when a ball sitting on top of a grassy hill rolls down the hill. The motionless ball has potential energy. Once the ball starts to roll down the hill, new kinetic energy is made. As the ball rolls across the grass, it slows down. The kinetic energy of the ball is converted to other forms of energy. Which best describes Alana's error?
B. Kinetic energy is not made; it is a result of energy transformation.
Which best explains why metal cooking utensils often have plastic coating on their handles?
B. Plastic reduces the transfer of thermal energy to hands holding the utensils.
What label should Mateo place in the marked cell?
B. Provides electrical energy
Mammals are a large group of animals that includes humans, apes, dolphins, bears, bats, cats, and much more. Which statement can be made about this information?
B. Some mammals use echolocation to avoid obstacles.
A doctor thinks a patient has an intussusception, in which a part of the intestine slides inside itself like the parts of a collapsible telescope. Which imaging technique is the doctor most likely to use? Explain.
B. Sonography is most likely because it has good resolution without radiation.
The equation below shows a general equation for a reaction, and the amounts of the substance are written underneath. AB + CD → AC + BD (15 g) (?) (?) (10 g) The total mass of the products is 50g. Which best completes the other two amounts?
B. The amount of CD is 35 g, and the amount of AC is 40 g.
A substance is boiled repeatedly and stirred, but the solute never mixes with the solvent. Which best describes why?
B. The chemical properties of the solute and solvent are different.
Sally is concerned about the X-ray images her dentist plans to take of her teeth. She has read that X-rays can cause tissue effects, such as skin reddening and hair loss. Which statement would best inform Sally of the level of risk?
B. The dentist uses X-ray radiography, which takes too short a time to cause those problems.
Two cars started at the same position and were driven through a city using different streets. The red car traveled north 2 miles, then east 4 miles, and then south 6 miles. The green car traveled south 4 miles and then east 4 miles. Both cars ended at the same location. Which best compares the motion of the cars?
B. The green car traveled a shorter distance, but the displacement of the cars was equal.
According to the law of reflection, which statement must be true?
B. The measure of angle B equals the measure of angle C.
An object is moving across a surface, but it does not gain or lose speed. Which best describes the object's force?
B. The net force is zero.
Which best explains how the coating works?
B. The surface of the coating is rough, so light that shines on it gets scattered in many directions.
How does a parallel circuit change when a branch is added?
B. The total resistance decreases, so the current in the circuit increases.
Which force best represents Fg?
B. The weight of a barbell acting on a weight lifter is 80 N.
A student shines a flashlight on the lens. Which best describes what happens when light rays exit the lens?
B. They are all refracted toward a central axis.
After the 1600s, how did observations of light being refracted change the way most scientists thought about light?
B. They began to believe that light acted as waves.
Which is a characteristic of all ions?
B. They have one overall charge.
At which point does the image appear?
B. X
The chart shows the amount of solute that fully dissolved when added to 500 ml of water. Which ranks the solutions in order of greatest to least solubility?
B. Y → X → Z
A candle's wick is the fabric string that holds the flame, and it burns down at a constant slow pace when the candle is lit. The wick is usually surrounded by wax. Which is the most important property of covalent compounds that makes them useful for making candle wax?
B. a low melting point
Hana fills a cup with sandy ocean water. She pours the mixture through a filter. What does she collect that passes through the filter?
B. a solution of salt in water
Which describes a value for density?
B. a value for mass, such as kg, divided by a value for volume, such as m3
What is the best way to arrange the magnets on the train and on the track so that the model train levitates?
B. flat, so that the north pole of the magnets on the train point up and the north poles of the magnets on the track point down
Which characteristic(s) makes ionic compounds useful as a building material?
B. hardness and brittleness
The sun emits electromagnetic waves at many frequencies, but mostly in the infrared, visible, and ultraviolet spectrums. What kind of energy is this?
B. radiant
What is most often given a value of zero to describe an object's position on a straight line?
B. reference point
When liquid silver nitrate and liquid sodium chloride are combined, solid silver chloride forms along with a new liquid, sodium nitrate. Which substance represents the precipitate?
B. silver chloride
Which element's symbol could replace the question mark in the diagram?
B. tellurium (Te)
Which best describes vibration?
B. the action of moving back and forth quickly and steadily
Based on the location of nitrogen (N) on the periodic table, how many additional electrons does a nitrogen atom need in its valence shell to satisfy the octet rule when it forms bonds?
B. three
A wave is traveling at 36 m/s. If its wavelength is 12 m, how many times does a wavelength move across a set point every second?
B. three times
The use of radioisotope imaging is best suited for which procedure?
B. to monitor the function of an enzyme in the cells of the pancreas
Which is the best example of a force counteracting Fp?
B. two children pulling apart a wishbone
When mixed, which states of matter form only a homogeneous mixture?
B. two gases
Isla's change in velocity is 30 m/s, and Hazel has the same change in velocity. Which best explains why they would have different accelerations?
B. Isla had a different time than Hazel.
Greg is in a bike race. At mile marker four (out of ten), his speed was measured at 13.5 mph. Which best describes the measured number?
B. It is the instantaneous speed of the bike rider.
Sometimes, the net force acting on an object is zero. Balanced forces are forces that combine to produce a net force of zero. When the forces on an object are balanced, the net force is zero and there is no change in the object's motion
Balanced Forces
The Rocket Club is planning to launch a pair of model rockets. The table lists the rocket bodies and engines that are available. Based on Newton's laws of motion, which combination of rocket bodies and engines will result in the acceleration of 40 m/s2 at the start of the launch?
Body 1 + Engine 2
The Rocket Club is planning to launch a pair of model rockets. The table lists the rocket bodies and engines that are available. Based on Newton's laws of motion, which combination of rocket bodies and engines will result in the acceleration of 40 m/s2 at the start of the launch?
Body 1 + Engine 2
Based on the information in the table, which elements are most likely in the same periods of the periodic table?
Boron and carbon are likely together in one period because they have very close atomic numbers, while gallium and germanium are likely together in another period because they have very close atomic numbers.
Fluorine (F) and bromine (Br) are in the same group on the periodic table. How do atoms of these elements compare when they form bonds?
Both a fluorine atom and a bromine atom gain one electron, and both atoms become stable.
Which explains the information needed to calculate speed and velocity?
Both require time, but velocity requires displacement and speed requires distance.
Which are the spectator ions in the following reaction? H₃O⁺ + Br + K⁺ + OH⁻ → K⁺ + Br + 2H₂O
Br and K⁺
What symbol would best represent an electric fan in an electric circuit?
C.
When discussing Newton's laws of motion, which terms do people most likely use when talking about Newton's third law of motion?
C. "action" and "reaction"
The graph represents velocity over time. What is the acceleration?
C. 0.2 m/s2
Sonya is playing a board game, and each space on the board game measures 1 centimeter. She moves her game token 5 spaces up from the start position. Then she moves it 5 spaces to the left. Finally, Sonya moves her token 2 spaces down. What is the total distance the token moved?
C. 12 cm
Rounded to the nearest whole number, what is the atomic mass of platinum?
C. 195
Which balances the equation Mg + O2→ MgO?
C. 2Mg + O2 → 2MgO
Where will the image of the paper clip appear to the observer?
C. 3
Two carts collide and bounce apart. Cart 1 had a momentum of -6 kg • m/s before the collision. Cart 2 had a momentum of 10 kg • m/s before the collision. What is the total momentum of the carts after the collision?
C. 4 kg • m/s
A car has a momentum of 20,000 kg • m/s. What would the car's momentum be if its velocity doubles?
C. 40,000 kg • m/s
A car is traveling in a race. The car went from the initial velocity of 35 m/s to the final velocity of 65 m/s in 5 seconds. What is the acceleration?
C. 6 m/s2
If velocity is positive, which would most likely yield a negative acceleration?
C. An initial velocity that is faster than a final velocity.
Which is best supported by the data in the chart?
C. Current X has a lower potential difference than Current Y.
Which shows the correct order of steps during the formation of an ionic bond?
C. Electrons are transferred → Ions form → Ions are attracted to each other
If the kinetic and potential energy in a system are equal, then the potential energy increases. What happens as a result?
C. Energy of motion decreases.
Jill is pushing a box across the floor. Which represents the upward force perpendicular to the floor?
C. FN
How should Sal correct his diagram?
C. He should add a single dot below the symbol.
Iodine and potassium form an ionic bond. Iodine has seven electrons in its outer shell, and potassium has one electron in its outer shell. Which conclusion is best supported by this information?
C. Iodine becomes an ion with a negative 1 charge.
Which best describes a benefit of using lasers instead of traditional cutting machines?
C. Lasers save time by cutting through more layers of fabric.
Cleo stated that light travels through air in straight paths, and when it moves from air to water, light changes direction, speeds up, and bends toward the normal. Which statement best describes Cleo's mistake?
C. Light slows down when it moves from air into water.
Lead is malleable, so it can be pounded into flat sheets without breaking. How does the bonding within lead help to explain this property?
C. Metallic bonds involve many valence electrons shared by many atoms, so the bonds can move around as the metal is pounded.
In what way is Model A better than Model B?
C. Model A shows the three-dimensional shape of the molecule, but Model B does not.
In what way is Model B better than Model A?
C. Model B shows how the atoms in the molecule are connected, but Model A does not.
Which is most likely a covalent compound?
C. NH5
What label should Patty place in the marked cell?
C. Resistor
How do Newton's laws of motion explain why it is important to keep the ice smooth on a hockey rink so that players can pass a puck as quickly as possible?
C. Smooth ice reduces the unbalanced forces that would slow the hockey puck.
Hiro rubs an inflated balloon on his hair, and his hair sticks to the balloon. As he moves the balloon away from his head, how does the electric force change?
C. The electric force decreases because the distance increases.
How does light interact with the surface of a rough stone?
C. The light reflects from the surface of the stone and does not form a clear image.
A sample of a solid nonmetal is compared to a sample of a solid metal. Both samples have the same volume. What is the most likely difference between the two samples?
C. The metal has more mass.
Jill uses a magnet to pick up a nail. Then, she touches the nail to a paper clip and picks up the paper clip. What will most likely happen when she pulls the magnet away from the nail?
C. The paper clip will fall off of the nail because the nail was only a temporary magnet.
Laptop computers are made with batteries, but they must also be plugged into outlets to charge the batteries. Which is true regarding laptops?
C. They can run on either direct or alternating current.
Wave A is being decreased in temperature, and Wave B is moving from a liquid to a gas medium. Which statement can be made about both waves?
C. They will slow down.
If humans cannot see ultraviolet waves, how can ultraviolet light be used to gather evidence of a crime?
C. Ultraviolet light causes substances to fluoresce and give off visible light.
Which order of pictures places molecules with the most amount of motion to the least amount of motion?
C. Y → Z → X
If the current in each wire is the same, which wire produces the strongest magnetic field?
C. a 1-mm-thick coiled wire with ten loops
Which scenario best describes motion?
C. a ball rolling from point A to point B
Which activity directly converts energy from the Sun into chemical energy?
C. a bean plant making its own food to grow
What causes the poles of the electromagnet in an audio speaker to repeatedly switch directions?
C. a current that rapidly switches direction
What causes the electric charges to flow from one end of the battery to the other?
C. a difference in electric potential
Which is an example of negative acceleration?
C. a skateboarder who reduces speed when moving up a hill
Which of these would most likely cause a sound wave?
C. a spoon hitting the side of a bowl while mixing
Which material most likely gets the warmest when placed in the Sun?
C. brown mulch
What kind of energy involves the flow of positive charges?
C. electrical
Alai is comparing the physical property of two materials. He is hitting each with a hammer to observe what happens. What physical property of the materials is Alai most likely observing?
C. hardness
Based on the graph of velocity over time, which could be the initial velocity and the final velocity for this graph?
C. initial = 2.5 m/s; final = 2.5 m/s
Luis is helping his parents paint a border around the walls of a room. He uses a stencil to repeat the same design on each wall to form one long grapevine with a bunch of grapes every foot along its length. What type of chemical reaction does this best model?
C. polymerization
Which symbol and unit of measurement are used for voltage?
C. symbol: V; unit: V
Which parts of an electric generator are connected?
C. the armature and axle
Which device provides electrical energy to run an electric circuit?
C. the battery
What is the purpose of step 1?
C. to magnetize the needle
Which set of terms best defines what affects kinetic energy and potential energy, respectively?
C. velocity, height
Jaipal measures a circuit at 1.2 A and 24Ω . Using Ohm's law, what can he calculate for the circuit?
C. voltage (V)
A plastic rod becomes negatively charged when it is rubbed with a piece of wool. How does the rod become charged?
C. Electrons move from the wool to the rod.
The graph depicts the velocity and times of Elan and Anna during a race. Which best depicts the data?
C. From 6 to 8 seconds, Elan accelerated faster than Anna.
Which equations are balanced? Check all that apply.
C3H8 + 5O2→ 4H2O + 3CO2 Zn + 2HCl → ZnCl2 + H2 3Ca(OH)2 + 2H3PO4→ Ca3(PO4)2 + 6H2O 4Al + 3O2→ 2Al2O3
There are several ways to model a compound. One type of model is shown. What is the chemical formula for the molecule modeled?
C6H12O2
What is the chemical formula for carbon tetrafluoride?
CF4
What else is produced when sodium carbonate decomposes? Na2CO3 → Na2O +
CO2
A cannon recoils from launching a cannonball, the speed of the cannon's recoil is small because
Cannon has far more mass than cannonball
The graph represents velocity vs. time for Carla. Which best describes the graph?
Carla slowed down in the beginning of her trip, stopped, and then sped up.
Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below. What experimental evidence led to the development of this atomic model from the one before it?
Cathode rays were bent in the same way whenever a magnet was brought near them.
he graph below shows how solubility changes with temperature. mc025-1.jpg Which solutions would be classified as supersaturated if they each contained 30 g of solute per 100 g of water and were cooled from 70°C to 40°C?
Ce2(SO4)3 and KClO3
Which statement best describes a physical change?
Changes can occur to physical properties of a substance, but the chemical composition of the substance remains the same.
Three students are working with different substances to measure the chemical changes that occur. Chao is working with milk, Mia is working with carbon dioxide gas, and Ezra is working with rock. Which would best describe the way to treat each substance to get a faster reaction?
Chao should change the temperature, Mia should adjust the pressure, and Ezra should increase the surface area.
Which statement best describes chemical properties of matter?
Chemical properties, such as combustibility, are generally observed as the identity of a substance changes and one or more new substances form
Carla is making two drinks. She is making one hot chocolate and one chocolate milk. Which best describes the agitation needed to make sure the cocoa powder is mixed in well?
Chocolate milk would require more agitation than hot chocolate does.
A situation in which two objects in close contact exchange energy and momentum.
Collision
Fog is a __{ composed of water droplets in air.
Colloid
The table represents the speed of a car in a northern direction over several seconds. Column 1 would be on the x-axis, and Column 2 would be on the y-axis. Which best lists the titles of each column?
Column 1 should be titled "Time," and Column 2 should be titled "Velocity."
Under certain conditions, collisions obey the law of conservation of momentum. Conservation of Momentum does not increase or decrease. Imagine two cars colliding with one another. If the two cars are apart of a closed system, then momentum is conserved. A closed system means other objects and forces cannot enter or leave a system. Thus, if we consider the two cars as a closed system, the cars can exert forces on each other. But overall, the total momentum of the system is conserved. In a closed system, the loss of momentum of one object equals the gain in momentum of another object- momentum is conserved
Conservation of Momentum
The momentum of an object, or set of objects (system), remains the same if it is left alone. Within such a system, momentum is said to be conserved.
Conservation of momentum
Pierce conducts an experiment in which waves collide in a way that the energy increases, which means that ______________ has occurred
Constructive interference
A company that manufactures cookware has conducted numerous trials to see which metal needs the least amount of energy (measured in Joules, J) to be raised to high temperatures, and records the averages in a table. Which claim will this company most likely make?
Copper pans are the most energy-efficient cookware, but they cost the most.
Which label could be written in the area marked X?
D "Uses a convex eyepiece lens"
Which graph would match the same type of movement that the graph shows?
D.
The surface areas of four solutes are 2 mm2, 6 mm2, 10 mm2, and 4 mm2. Which solute will dissolve the quickest?
D. 10 mm2
A force of 5 N accelerates an object. The object's mass is 50 g. What is the acceleration of the object? (Formula: F=ma)
D. 100 m/s2
The amount of oxygen in the reactants is 4 atoms. In the products, the oxygen is distributed to water (H2O) and O2 gas. Which coefficients would be placed in front of water and oxygen?
D. 2 in front of water and 1 in front of oxygen
What is the resistance of a light bulb if a potential difference of 120 V will produce a current of 0.5 A in the bulb?
D. 240 Ω
A machine has a mechanical advantage of 4.5. What force is put out by the machine if the force applied to the machine is 800 N?
D. 3600 N
Ariana is accelerating her car at 4.6 m/s2. It took her 10 seconds to reach this acceleration. Her starting velocity was 0 m/s. What was her final velocity?
D. 46 m/s
A track begins at 0 meters and has a total distance of 100 meters. Juliet starts at the 10-meter mark while practicing for a race. After running 45 meters, how far is she from the beginning of the track?
D. 55 meters
Reggie and Charlotte are baking oatmeal cookies. They dip the baked cookies in melted chocolate. The chocolate cools to form a hardened coating. Reggie argues the entire chocolate-covered cookie has undergone a chemical change. Charlotte disagrees, saying only the original oatmeal cookie has undergone a chemical change, not the chocolate coating. Who is correct?
D. Charlotte, because baking causes a chemical change, but melting objects is a non-chemical change.
Emmett is lifting a box vertically. Which forces are necessary for calculating the total force?
D. Fp and Fg
Carl makes the table below to determine the number of atoms of each element in the chemical formula 4Ca(ClO3)2. What mistake did Carl make?
D. He did not multiply the chlorine and oxygen atoms by the coefficient 4.
A substance did not change its chemical nature in a reaction. Which most likely describes the reaction?
D. It was frozen.
An electroscope is a device that detects charge on objects that touch it or are brought near it. John rubs a piece of cotton fabric on a plastic rod and then touches the rod to the electroscope. What methods of charging does John use?
D. John charges the rod through friction, then charges the electroscope through conduction.
Pedro wants to create a chemical reaction between oil and water. He adds oil to a beaker of water and notices that the liquids do not mix. He then shakes the beaker and the drops of oil become suspended through the water for a few moments before returning to their separate layers. Did Pedro succeed in creating a chemical change?
D. No, because no new substances were formed.
Which is the balanced equation for S8 + O2 → SO2?
D. S8 + 8O2 → 8SO2
Adita lifts a book from the floor, carries it across the room, and places it on a high shelf. When is Adita doing work on the book?
D. She does work as she picks up the book and as she lifts it to the shelf.
Which statement explains the treatments?
D. Substance 1 was activated by the heat and inactivated by ice, Substance 2 was activated by the change in concentration, and Substance 3 increased the surface area.
Which best describes the law of conservation of mass?
D. The mass of the reactants and products is equal and is not dependent on the physical state of the substances.
Maria examines a mixture that appears to be the same throughout. However, when she looks at a sample using a magnifying lens, she can see small droplets of liquid surrounded by another liquid. Which conclusion best fits her observations?
D. The mixture is a colloid because two different substances can be seen in a small sample.
Which statement should he place in the region marked X?
D. The objects have the same charge.
How do the lights in a series circuit behave when one bulb burns out?
D. The rest of the bulbs stop shining and shut off.
Which statement correctly compares the speed of light?
D. The speed of light in glass is slower than the speed of light through space.
Hydrochloric acid and sodium hydroxide can be combined in equal ratios to form sodium chloride and water. Which best explains the reaction?
D. The total volume produced by combining hydrochloric acid and sodium hydroxide will result in the same volume of sodium chloride and water.
Which best describes what all of the observations have in common?
D. They involve changes in energy.
What mistake did Gino make?
D. Ultraviolet light should have a short wavelength, not a long wavelength.
Based on the field lines, what are the charges of the objects?
D. X: positive Y: positive
Which lists the objects in order, from least to greatest momentum?
D. Y, W, X, Z
If all the canisters had the same amount of particles, which canister would have the fastest moving particles?
D. Z
Keesha conducts an experiment by pouring equal amounts of boiling water into four containers. The containers are the same size and shape, but they are made of different materials. The chart lists the containers according to their materials. Using protective gloves, Keesha carefully touches each container immediately after pouring the water. Which container was likely the hottest?
D. Z
What is required for an electric charge to flow through a wire?
D. a difference in electric potential
What is the correct classification of a mixture in which both a solid and a liquid are visible?
D. a heterogeneous mixture and a suspension
Which is a compound machine?
D. a pair of scissors
Julie finds a snail on the sidewalk and wants to know whether or not the snail moves throughout the day. She places a single mark on the sidewalk next to the snail. What will Julie use the mark for initially?
D. acting as a reference point for detecting motion
Which element's symbol could replace the question mark in the diagram?
D. arsenic (As)
In carbon dioxide (CO2), there are two oxygen atoms for each carbon atom. Each oxygen atom forms a double bond with carbon, so the molecule is formed by two double bonds. Two double bonds means that the total number of electrons being shared in the molecule is
D. eight.
Green plants need light in order to survive. Structures in the leaves absorb light, which in turn, helps plants make their own food. Under which color of light will plants be least likely to make food?
D. green
Atoms of which elements form bonds without satisfying the octet rule?
D. helium (He) and hydrogen (H)
Which change would cause the needle on the ammeter to point to the left of the zero?
D. moving the wire downward through the magnetic field
During a camping trip, Sierra collected dry branches and broke them into smaller pieces. She then placed the sticks in a fire pit and used a match to light the sticks on fire. Next, she propped a metal pan of water over the fire and heated it until the water boiled. Which list correctly describes physical and chemical changes that occurred in this scenario?
D. physical changes: breaking sticks, boiling water chemical change: lighting the fire
Keisha told her friend that she can get to the town library by walking one mile east, turning left, and then walking a half a mile north. Which best describes how Keisha can improve these instructions to better help her friend find the library?
D. providing a reference point to follow
Solar-powered cars use energy from the Sun to work. A panel on the car absorbs light energy from the Sun, which then generates an electric current. This electric current, in turn, allows the car to move. Which shows the correct order of energy transformations that take place in a solar-powered car?
D. radiant, electrical, mechanical
Ellen needs to move a heavy box across the floor and then place it on a shelf that is four feet above the floor. Which use of machines would most likely require the least amount of force in order to get the box on the shelf?
D. rolling the box across the floor in a cart and then using a pulley
Which atom is most likely to accept electrons to form an ionic bond?
D. sulfur, a nonmetal with 6 valence electrons
Which symbol and unit of measurement are used for electric current?
D. symbol: I; unit: A
What is the Compact Muon Solenoid used to study?
D. the particles emitted when atoms collide
Ariana is accelerating her car at 4.6 m/s2. It took her 10 seconds to reach this acceleration. Her starting velocity was 0 m/s. What was her final velocity?
D. 46 m/s
Kiley went 5.7 km/h north and then went 5.8 km/h west. From start to finish, she went 8.1 km/h northwest. Which best describes her numbers?
D. 5.7 km/h north and 5.8 km/h west are instantaneous velocities, while 8.1 km/h northwest is the average velocity.
Which best compares a nondigital and a digital camera?
D. A nondigital camera uses film to record images, and a digital camera uses sensors.
How are reflecting telescopes similar to devices that produce laser light?
D. Both use mirrors to reflect a beam of light.
Which best explains why one laser beam might appear blue and another laser beam might appear red?
D. Each laser beam is made up of one specific wavelength of light.
The chart shows the times and accelerations for three drivers. Which lists them from greatest to lowest change in velocity?
D. Kira → Diego → Dustin
Aretha measures a circuit at 110 V and 240Ω . Using Ohm's law, what can she calculate for the circuit?
D. current
Denise is riding her bike and falls to the ground. During the collision, she hits both grass and cement. Which best explains why Denise had fewer injuries to the area of her body that hit the grass?
D.The grass extends the time of the collision.
The model of the atom has changed as scientists have gathered new evidence. Four models of the atom are shown below, but one important model is missing. Which atomic model is missing from this set?
Dalton's model
The graph shows two runners participating in a race. Which best describes the runners?
Daniela had a 5 meter head start, and Leonard caught up to her at 25 meters.
A chemical reaction that has the general formula of AB → A + B is best classified as a ____________ reaction.
Decomposition
Louis Pasteur discovered that germs cause illnesses. He invented a process called pasteurization to help kill germs in food. When government agencies began requiring pasteurization in food, society most likely observed a(n) .
Decrease food Ill
What discoveries are each of the people famous for?
Democritus: naming the atom as identical indivisable units. Aristotle: didn't believe you could ever stop dividing. Dalton: performed experiments to prove atom existed. Thompson: discovered smaller particles inside atom (electrons). Rutherford: revised model to include nucleus. Bohr: electrons orbit nucleus. Schrodinger: electrons orbit in clouds. Chadwick: discovered neutrons.
Final velocity depends on what?
Depends on initial velocity, acceleration and time.
Which change of state is shown in the model?
Deposition
________ investigations never involve hypotheses.
Descriptive
Equation for displacement with constant acceleration
Displacement equals 1/2 x (initial velocity + final velocity) x time interval
A negative value for the acceleration does not always indicate what?
Does not always indicate a decrease in speed. For example, if the train were moving in the negative direction, the acceleration would be negative or the train gained speed to leave the station and positive when the train lost speed to enter a station
Which source is most likely an authority on the subject?
Dr. Patel, a cardiologist, presents her findings on heart disease.
-11 m/s^2
During a test crash, an airbag inflates to stop a dummy's forward motion. The dummy's mass is 75 kg. If the net force on the dummy is 825 N toward the rear of the car, what is the dummy's deceleration?
What do an electron and a neutron have in common?
Each particle exists inside an atom.
Read the article by Michael Fumento, writer for the New York Post editorial blog, who does not support global warming. Back in 2005 I and others reviewed the entire hurricane record, which goes back over a century, and found no increase of any kind. Yes, we sometimes get bad storms—but no frequently now than in the past. The advocates simply ignored that evidence. Fact is, the earth was cooling and warming long before greenhouse gases could have been a factor. The [global warming supporters] have been proved wrong time and time again. Which best describes the reliability of the source?
Editorial blogs are considered an unreliable source because the author may not have a science background.
Strength or energy as an attribute of physical action or movement. It can cause a resting object to move, or it can accelerate a moving object by changing the object's speed or direction. Wind pushing against a person can cause them to slow down, or even change direction
Force
kevin rolls a 9 kg bowling ball slowly that it stops. The impulse necessary to stop this bowling ball rolling at 3 m/s is?
Ft= -27 N.S
The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance gain energy during a change of state. Before the change, the atoms are close together and cannot slide past one another. After the change, the substance can fill its container.
Gas.
Force that pulls all objects together "closer the objects, the harder the pull" "greater the mass, larger the pull"; acceleration due to gravity is 9.8 m/s/s on earth (if it weren't for air resistance).
Gravity
The force that one massive object exerts to attract another object is called _______.
Gravity
Which describes an object in projectile motion? Check all that apply.
Gravity acts to pull the object down. The object's inertia carries it forward. The path of the object is curved.
Which statement describes gravity? Check all that apply.
Gravity is the force that pulls objects toward Earth's center. Gravitational pull between two objects increases as the mass of one increases. Gravitational pull decreases when the distance between two objects increases.
Greater impulse equals
Greater change in momentum
When a car comes to a full stop after hitting a brick wall and hitting a water filled barrel, the force that stops the momentum is: greater hitting the wall, greater hitting the barrel, the same momentum change in both.
Greater hitting the wall
The impulse needed to bring an object to a stop and then "throw it back again" (bounce) is
Greater than the impulse needed to stop the object
Formaldehyde is an organic compound. Each molecule includes two hydrogen (H) atoms, one oxygen (O) atom, and one carbon (C) atom. Below are the dot structures for each of these elements. Which diagram shows how the covalent bonds most likely form in a formaldehyde molecule?
H | .. C = O | .. H
What else is produced during the combustion of propane, C3H8? C3H8 + 5O2 → 3CO2 + 4 |____|
H2O
The more energy a wave carries, the _____ its amplitude.
HIGHER
The Venn diagram compares protons with neutrons. Which shared property belongs in the region marked "B"?
Has mass of 1 amu
For a science fair project about food and chemistry, Bill looks around his kitchen for examples of covalent compounds. What evidence can Bill use in his project to show that water (H2O) acts like other covalent compounds?
He can demonstrate that water is a liquid with a definite volume.
Carl makes the table below to determine the number of atoms of each element in the chemical formula 4Ca(ClO3)2.
He did not multiply the chlorine and oxygen atoms by the coefficient 4.
Henry mixed salt and water together in a cup until he observed a clear solution. He measured the mass of the solution. Then he placed the cup outside for several sunny days during the summer. After a week, he observed that only solid salt remained in the cup and the mass had decreased. Henry concluded that a physical and chemical change occurred in this investigation.
He is incorrect. Dissolving salt in water and evaporation of the water are both physical changes. The reappearance of salt is evidence that the change was reversible by a physical change, so it could not be a chemical change.
Is has properties similar to the noble gases.
Helium only has 2 electrons why is it grouped with the noble gases who have 8 valence electrons?
Separating by density
Heterogeneous mixtures can also be separated on the basis of particle density. Did you know that your blood is a mixture? It contains a component called plasma (which is mostly water) and three different types of cells. When you have a blood sample drawn at a medical clinic, it will probably be put into a machine called a centrifuge. This machine spins the sample tubes at a very high rate. As a result, the more dense materials move to the bottom of the tube, and the less dense plasma moves to the top.
Hunter's velocity was 4.5 m/s. At the end of his race, his velocity was the same. Which best describes his movement?
His acceleration is zero.
When air resistance acts, acceleration during a fall will be less than g because air resistance affects the motion of the falling objects by slowing it down.
How does air resistance affect the acceleration of a falling object?
What is the first step in every physics problem?
Identify what the problem is asking.
The diagrams show objects' gravitational pull toward each other. Which statement describes the relationship between diagram X and Y?
If the masses of the objects increase, then the force between them also increases.
Suppose that a substance in a beaker is heated over a burner in a science lab. Which observation would most likely indicate that a chemical change has occurred in the substance?
If the substance is a liquid or solid, production of an odor would indicate a chemical change.
If you hit a solid wall instead of a safer barrier, you would have a greater chance of injury because
Impulse force is large and impulse time is small
You have a less chance of being hurt if your speeding car hits a haystack instead of a mall because
Impulse force is small and impulse time is large
Two objects sticking to each other.
Inelastic Collision: what it looks like
Only momentum is conserved. Kinetic Energy is lost in the forms of heat and sound
Inelastic Collisions conserves
A tendency to do nothing or to remain unchanged. Newton's first law of motion is sometimes called the law of inertia
Inertia
Investigations were carried out in a science lab to explore the topic of chemical and physical changes. Investigation A Step 1. Add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible. Step 2. Heat the salt solution on a burner until only a white solid remains. Investigation B Step 1. Mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible. Step 2. Heat the sugar solution on a burner until the solution thickens and turns brown.
Investigation B, Step 2 only
Investigations were carried out in a science lab to explore the topic of chemical and physical changes. Investigation A Step 1. Add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible. Step 2. Heat the salt solution on a burner until only a white solid remains. Investigation B Step 1. Mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible. Step 2. Heat the sugar solution on a burner until the solution thickens and turns brown. In which step(s) did a chemical change most likely occur?
Investigation B, Step 2 only
Investigations were carried out in a science lab to explore the topic of chemical and physical changes. Investigation A Step 1. Add 5 tsp. salt to 100 ml warm water and stir until most or all of the salt is no longer visible. Step 2. Heat the salt solution on a burner until only a white solid remains. Investigation B Step 1. Mix 10 tsp. white sugar into 100 ml water and stir until most or all of the sugar is no longer visible. Step 2. Heat the sugar solution on a burner until the solution thickens and turns brown. In which step(s) did a chemical change most likely occur
Investigation B, Step 2 only
p = mv. If the mass is doubled what happens to the momentum?
It doubles
Football helmets are made with padding that helps reduce head injuries when a player collides with an object. Which best explains how the padding reduces injuries?
It extends the time of the collision.
What is the reason a cannon has a smaller recoil (acceleration) than a cannonball
It has a larger mass
A potassium atom (atomic number 19) and a bromine atom (atomic number 35) can form a chemical bond through a transfer of one electron. The potassium ion that forms has 18 electrons. What best describes the bromide ion that forms?
It is a negative ion that has one more valence electron than a neutral bromine atom.
Two objects collide and bounce apart. Assuming no outside forces act on the system, which best describes the total momentum after the collision?
It is always the same as it was before the collision.
Min is asked to balance the equation below. Original: Ca3P2 + H2O → Ca(OH)2 + PH3 Min's result: Ca3P2 + H2O → Ca3(OH)2 + PH3 Which best describes Min's method for balancing the chemical equation?
It is incorrect, because the identity of the original product has changed.
Potassium chlorate decomposes to produce 20 g of solid potassium chloride. Oxygen gas is also produced. Which best describes the mass of oxygen?
It is less than the mass of potassium chlorate.
What does the chemical formula CaCl2 show about the compound it represents?
It is made up of two elements.
Greg is in a bike race. At mile marker four (out of ten), his speed was measured at 13.5 mph. Which best describes the measured number?
It is the instantaneous speed of the bike rider.
Which is a characteristic of the part of the atom marked "A"?
It is very dense. or It contains most of the mass.
Uranium is a type of atom. In special circumstances that usually involve high amounts of energy, uranium can be broken. When this occurs, different pieces of the original atom remain, including a substance called plutonium. Which statement most likely describes plutonium?
It must be a different kind of atom.
The simple model below is a neutral magnesium (Mg) atom with the element's most common mass number. What must happen to an atom of magnesium in order to become a magnesium ion Mg+2?
It must lose two electrons and become an ion.
Which characteristic should a good scientific question have?
It should be based on observations instead of just imagination.
Which best explains why replicating an experiment should be done by someone other than the person who originally did the experiment?
It shows that the experiment is designed properly.
Which describes how a centrifuge separates a mixture?
It spins a sample to separate based on density.
What happens to the total mass of a substance undergoing a physical change?
It stays the same.
What will most likely happen if a sound wave moves from the air through a solid?
It will increase in speed.
A compound that releases hydrogen ions in solution would most likely have which chemical property?
It would react with metals to form hydrogen gas.
Anya knows the velocity of an object. What else does she need to know in order to find the object's momentum
It's mass
Based on the information shown, which statement about the subatomic particle must be correct?
Its location is in the nucleus, because the particle is a proton or a neutron.
What discovery demonstrated that atoms are not the smallest particles?
J.J. Thomson discovery of electrons inside atoms.
In his model the electrons are scattered throughout a ball of positive charge.
JJ Thomson
Two boxes need to be moved into storage. Jamal and Jude each want to move a box. The force of gravity on both the boxes is 50 N. Jamal is lifting with a force of 60 N, and Jude is lifting with a force of 45 N. Which best describes the movement of the boxes?
Jamal moved his box to storage, but Jude could not move his.
Momentum is not lost in a collision but can only be transferred
Law of Conservation of Momentum
Static, sliding, rolling, and fluid friction.
List the four types of friction.
If atoms energy during a change of state, they are pulled together by attractive forces and become more organized.
Lose
Forces are often easy to measure. The stretch of the spring in the scale depends on the amount of weight acting on it. Weight is a type of force
Measuring Force
Lead is malleable, so it can be pounded into flat sheets without breaking. How does the bonding within lead help to explain this property?
Metallic bonds involve many valence electrons shared by many atoms, so the bonds can move around as the metal is pounded.
What else is produced during the replacement reaction of magnesium and hydrochloric acid? Mg + 2HCl → H2 +
MgCl2
Momentum is the product of an object's mass and its velocity. The momentum for any object at rest is zero. You can calculate momentum by multiplying an object's mass(in kilograms) and its velocity(in meters per second). Momentum Formula Momentum = Mass x Velocity. Momentum is measured in units of kilogram-meters per second. (kg*m/s)
Momentum
Read the passage about the fluoridation of drinking water. Since the early 1960s, fluoride has been added to many sources of drinking water to prevent cavities in teeth. This is called fluoridation. There are some who say that this is unnecessary and increases the risk of cancer. In 1993, the Subcommittee on Health Effects of Ingested Fluoride of the National Research Council, part of the National Academy of Sciences, conducted an extensive study about the link between fluoridated drinking water and increased cancer risk. The study included data from more than 50 human disease studies and six animal studies. The Subcommittee concluded that none of the data showed a link between fluoridated drinking water and cancer. A 1999 report by the CDC supported these findings. The CDC report concluded that studies so far have produced "no credible evidence" of a link between fluoridated drinking water and an increased risk for cancer. Which information makes this article reliable?
More than 50 studies were conducted.
Which best explains Rob's error?
NOT A, C
What is the mechanical advantage of a machine that applies a force of 1000 N to an object when a force of 500 N is applied to the machine?
NOT A,. 0.5
Which device manages the flow of current in an electric circuit?
NOT A,C
Venn diagrams are used for comparing and contrasting topics. The overlapping sections show characteristics that the topics have in common, and the sections that are unique to each topic show the characteristics that apply to only that topic. This Venn diagram is comparing longitudinal waves and transverse waves. Where is the error in this Venn diagram?
NOT A. "Parallel" and "Perpendicular" are switched.
How does a convex mirror form an image?
NOT A. It bends the light toward a focal point.
Radioisotopes often emit one or more types of radiation, including alpha particles, beta particles, and gamma rays. The distance the radiation travels through matter before being absorbed increases in order from alpha to gamma. Which statement describes the best radioisotope that can be used for radioisotope imaging and for radionuclide therapy?
NOT A. It emits only gamma rays.
What happens to an iron bar when it is placed within the coils of a solenoid?
NOT A. It induces a current.
How is an image formed by a plane mirror?
NOT A. Light bounces off of the mirror and then appears to come from in front of the mirror.
Which statement best compares potential and kinetic energy?
NOT A. Objects always have more potential energy than kinetic energy.
Which of these indicates that a liquid has transferred thermal energy to the air?
NOT A. The liquid increases in temperature, and its particles lose kinetic energy.
Which conclusion is best supported by the data?
NOT A. The particles in substance W have a greater average kinetic energy than the particles in substance Z.
Which explains why conduction is unlikely when ice is placed on a freezer shelf?
NOT A. There is no direct contact.
Which statement is best supported by the table?
NOT A. Wave W is being reflected, Wave X is being refracted, and waves Y and Z are being diffracted.
Jenny is trying to describe a wave. Which example would be the best description?
NOT A. a toy car hitting a wall and bouncing back
What are two forms of mechanical energy?
NOT A. electrical and kinetic
In which part of the wave are the particles of the medium closer together?
NOT A. rarefactions
Which color of white light bends the most when it is refracted by a prism?
NOT A. red
Different kinds of lenses are used in eyeglasses to help people with eye conditions. Farsightedness is an eye condition in which distant objects appear clear but close objects appear blurry. Nearsightedness is an eye condition in which close objects appear clear but distant objects appear blurry. Which best describes the type of lens that would help someone with one of these eye conditions?
NOT B,C
What characteristic do all parts of the electromagnetic spectrum share?
NOT B,C
What is the resistance in the circuit?
NOT B. 1.8
What is the resistance of a clock if it has a current of 0.30 A and runs on a 9.0-V battery?
NOT B. 2.7 Ω
A lawnmower engine running for 20 min does 4,560,000 J of work. What is the power output of the engine? (Power: P = W/t)
NOT B. 228,000 W
What is the momentum of a 5 kg object that has a velocity of 1.2 m/s?
NOT B. 4.2 kg • m/s
Which describes the form of technology most likely being used by each person?
NOT B. Ali is using a radio, Megan is using a microphone, Kristoff is using a transmitter, and Jenna is using specialized headphones.
Which best describes Andre's error?
NOT B. Electromagnetic waves can only transfer energy over short distances.
Which best describes a difference between laser light and regular light?
NOT B. Laser light has a beam that spreads out.
How do radiography and sonography compare?
NOT B. Radiography uses X-rays, but sonography uses radio waves.
Kendra wants to use similes to describe the reflection and absorption of waves. Which pair of similes best fit?
NOT B. Reflection is like water soaking into a paper towel, and absorption is like bouncing a tennis ball.
Which of these would correct Sayid's error?
NOT B. Replace "travel in straight lines" with "move in curved paths."
Henry can lift a 200 N load 20 m up a ladder in 40 s. Ricardo can lift twice the load up one-half the distance in the same amount of time. Which comparison between Ricardo and Henry is correct?
NOT B. Ricardo exerted a greater force, did the same amount of work, and had a greater power output than Henry.
Which best describes how Makori can correct the error in his diagram?
NOT B. Switch the locations of the eyepiece lens and the objective lens.
Which best describes Zach's error?
NOT B. The atoms in the crystal do not release energy; they only absorb energy.
What happens when the thermal energy of a substance increases?
NOT B. The motion of the particles in the substance decreases, and the temperature of the substance increases.
What must be true about two objects for conduction to take place?
NOT B. The objects must be the same temperature and they must be in contact.
An ultrasound tech is trying to identify an object, but the screen of the machine is broken. Which statement best describes this situation?
NOT B. The sound wave will not be generated, so there will be no echoes received.
Which list shows the order in which white light passes through these substances, from fastest to slowest?
NOT B. W, X, Y, Z
Which object is least likely to allow light to pass through it?
NOT B. a clear water bottle
Which kinds of lenses are in a light microscope?
NOT B. a convex objective lens and a concave eyepiece lens
Tas watches as his uncle changes a flat tire on a car. His uncle raises the car using a machine called a jack. Each time his uncle pushes down on the jack handle, the car rises up. Tas sketches the jack and labels it using the symbols F, to represent force, and d, to represent distance. He uses large and small letters to compare the sizes of the forces and distances. Which set of labels is correct for the side of the jack that Tas's uncle pushes on?
NOT B. a small F and a small d
Which therapy is associated with light, but not sound?
NOT B. acoustically targeting the delivery of a drug
Pablo prepares to lift a barbell. During which stage of the lift does Pablo do work on the barbell?
NOT B. when he applies force to the barbell but has not moved it
What is the main disadvantage of parallel circuits?
NOT C, A
When sound is created, it travels to the ear through a
NOT C, A
Which of these will reflect light with the highest frequency?
NOT C, A
According to Newton's third law of motion, which are equal?
NOT C, A.
A compass needle normally points toward Earth's magnetic pole, which is near the North Pole. Which best explains why the needle moves away from the pole when it comes close to a current-carrying wire?
NOT C, B
Juan makes an adjustment to an electromagnet that causes the electromagnet to lose some of its strength. What did Juan most likely do?
NOT C, B
Samantha is viewing a real image formed by a lens of a diamond ring. Which must be true about the image?
NOT C, B
A light bulb has a resistance of 360Ω . What is the current in the bulb when it has a potential difference of 120 V across it?
NOT C, D
Zaccharias Janssen was a scientist who studied properties of light and invented one of the first compound microscopes in the late 1500s. Which property did Janssen most likely believe about light during the time of his invention?
NOT C, D
A bowling ball collides with a pin and pushes the pin toward the right. Which describes the reaction force?
NOT C, D.
A wave of infrared light has a speed of 6 m/s and a wavelength of 12 m. What is the frequency of this wave?
NOT C,D
A hair dryer has a resistance of 11.5Ω . What current does it conduct when it is plugged into a wall outlet that provides 120 V?
NOT C. 109 A
Which statement best describes why a machine is useful?
NOT C. A machine can decrease both the input force and the input distance needed to do a given amount of work.
How can mechanical waves help in the treatment of cancer?
NOT C. Beams of X-rays are targeted at a cancerous tumor from outside the body.
Which lists the students in order from the greatest amount of work done to the least? (Work: W = Fd)
NOT C. Bill, Chet, Mika, Sara
Why does green light slow down more than orange light does when passing through an object?
NOT C. Green light refracts less than orange light.
Henri draws a wave that has a 4 cm distance between the midpoint and the trough. Geri draws a wave that has an 8 cm vertical distance from the bottom of the trough to the top of the crest. Which statement best describes the energy in Henri and Geri's waves?
NOT C. Henri's wave and Geri's wave have the same amplitude, but Geri's has more energy.
Objects 1 and 2 collide and stick together. Which best describes the momentum of the resulting single object?
NOT C. It is equal to the momentum of object 1 minus the momentum of object 2.
A scientist designed a foam container to help keep frozen foods from melting. Which best explains how the foam works?
NOT C. It reduces the amount of thermal energy that is transferred from inside to outside the container.
Which describes how radiation moves?
NOT C. Radiation moves from a warm object to an object of the same temperature
An ultrasound machine is being used to try to identify potential kidney stones. The machine is working properly and no kidney stones are found. Which statement best describes this situation?
NOT C. The echoes will be made but will not be able to be received by the machine.
Carla did an experiment by placing a piece of smooth, clear glass and a piece of smooth, black stone under a lamp for twenty minutes. Which prediction will most likely be supported by Carla's experimental results?
NOT C. The glass will reflect all of the light after twenty minutes.
What error did Roshan make?
NOT C. The ray that goes parallel to the main axis after passing through the lens should also be parallel from the object to the lens.
How should Xander describe the reflection?
NOT C. The reflection of the candle in the concave mirror formed an upside-down virtual image that is smaller than the candle.
Cora, an electrician, wraps a copper wire with a thick plastic coating. What is she most likely trying to do?
NOT C. increase the voltage produced by the wire
Which imaging techniques capture real-time images?
NOT C. sonography and CT
Chang wants to build a circuit that will light up the bulb from a flashlight. Which component could Chang leave out and still light up the bulb?
NOT C. the wire
According to Ohm's law, which combination of units is the same as the unit for resistance?
NOT C. volt + ampere
What happens when light from the Sun passes through any type of matter?
NOT D, B
What kind of image does the lens in a camera produce?
NOT D, B
What do diffraction and refraction have in common?
NOT D,A
Which statement best describes how waves carry energy?
NOT D. Energy builds through the wave and is released at the end.
What is an advantage of series circuits?
NOT D. Light bulbs get dimmer as more bulbs are added.
How do radiography and fluoroscopy compare?
NOT D. Radiography uses ionizing radiation, but fluoroscopy does not.
A compass taken to Earth's moon does not point in a specific direction on the moon. What is the most likely reason for the difference between how the compass works on Earth and on the moon?
NOT D. The moon has no bodies of water.
A thermogram of a house shows high amounts of thermal energy around the windows but not around the roof. Which conclusion is best supported by the thermogram?
NOT D. The roof is not energy efficient, but the windows are.
Which best describes why a diamond ring will sometimes sparkle different colors in normal white light?
NOT D. destruction
The area on the thermometer marked with the letter A is called the ______.
NOT celsius
The chart show the masses and velocities of two colliding objects that stick together after a collision. According to the law of conservation of momentum, the momentum of the object after the collision is ______ kg • m/s.
NOT. 350
The graph below shows how solubility changes with temperature. mc026-1.jpg Which two solutions have similar solubilities at 40°C?
Na2HAsO4 and Na2SO4
The charges for four ions are sodium (Na) +1, calcium (Ca) +2, fluorine (F) -1, and sulfur (S) -2. Which would be an ionic bond that could form from any of these ions?
Na2S
If the products of a chemical reaction are sodium chloride and oxygen gas, what was the reactant?
NaClO3
Based on the synthesis reaction, what would the product of the reaction be? NaPO3 + CuO → ?
NaCuPO4
These are strong bases?
NaOH KOH
The salt sodium sulfate, Na₂SO₄, can be formed by a reaction between
NaOH and H₂SO₄.
An unbalanced force causes an object's velocity to change. In other words, the object accelerates. Newton also learned that the acceleration of an object depends upon its mass. According to Newton's second law of motion, the acceleration of an object is equal to the net force acting on it divided by the object's mass. Thus, doubling the mass of an object cuts its acceleration in half. The acceleration of an object is always in the same direction as the net force. Note that Newton's second law also applies when a net force acts in the direction opposite to the object's motion
Newton's Second Law of Motion
Marco wants to investigate the chemical properties of sodium bicarbonate, or baking soda. He plans to carry out the tests below. Test 1: Mix a teaspoon of sodium bicarbonate into a cup of warm water to see if it dissolves. Test 2: Mix a teaspoon of sodium bicarbonate into a cup of vinegar to see if it fizzes. Test 3: Heat a teaspoon of sodium bicarbonate in the oven to see if its melting point is less than 400 degrees Fahrenheit. Which statement provides the best assessment of his tests?
Only Test 2 will indicate a chemical property of sodium bicarbonate. Tests 1 and 3 will show a physical property of the substance.
Donald is writing a chemical name from a chemical formula. He has just identified that there are five atoms of oxygen bonded with two atoms of phosphorus. What is the chemical name of Donald's compound?
P2O5
The element phosporus is located to the right of the element magnesium along the same period in the periodic table. Which best describes the relationship of the elements?
Phosphorus has a larger atomic mass.
Which is a scientific claim?
Plants fertilized once per week with Super Plant Food Formula have been shown in testing to produce twice as much fruit as plants that are not.
Leslie wants to know which advertising medium works best to promote her electronics store. She surveys her customers over a weekend and creates a bar graph. Based on her survey, which advertising mediums will work best to publicize Leslie's in-store specials?
Printed flyer's and Internet
The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance lose energy during a change of state. Before the change, the atoms are close together but are able to slide past one another.
Q
Why is reaching activation energy necessary?
Reactants require a minimum amount of energy to start to break a chemical bond.
The first chart shows the effect of the normal breakdown of material from reactants to products. The second chart shows the same reaction but with an added modification. Which statement best describes the difference between the charts?
Reaction B has an enzyme.
How can impulse affect the impact of a collision?
Reduce force of impact Make stopping time of impact longer
The law of conservation of momentum states that, if left alone, the total momentum of two interacting objects that make up a system ______.
Remains the same.
Is the force resisting the motion when a body (such as a ball, tire, or wheel) rolls on a surface. When a round object rolls across a flat floor, both the object and the floor are bent slightly out of shape. This change in shape at the point of contact is the cause of friction
Rolling Friction
After being forced to leave school because of a plague outbreak in London in 1665, Newton began to build on the work of scientists like Galileo. He published his results many years later in a book called Principia. In this work he defined mass and force, and also introduced his laws of motion
SIr Isaac Newton
View the graph of sun hours in a city. It can be predicted that in the following year, this city can expect the hours of sunshine to significantly increase after which month?
September
Elena makes the table below to determine the number of atoms of each element in the chemical formula 3(NH4)2SO4. What mistake did Elena make?
She should not have multiplied the sulfur atoms by the subscript 4.
The density of solid aluminum is 2.70 . If a 1g piece of aluminum is dropped in a cup of water, it will . (The density of water is 1.00 g/cm3 )
Sink
Refers to the resistance created by two objects sliding against each other. This can also be called kinetic friction. It is intended to stop an object from moving. If you push an object and it begins to move, it is no longer acting on the object. Instead, a smaller friction force called this acts on the sliding object
Sliding Friction
As the train approaches the station, its velocity decreases over time. The graph segment representing this motion appears how?
Slopes down to the right, at point C on the graph.
A cannonball is launched from a cannon. The ACCELERATION on the cannon compared to the cannonball is
Smaller than on the cannonball
Venn diagrams are used for comparing and contrasting different topics. The overlapping sections show characteristics that the topics have in common, and the sections that are unique to each topic show the characteristics apply to only that topic. Which Venn diagram accurately describes what characteristics of solids, liquids, and gasses could be added to this diagram?
Solid: Definite shape, Most Dense Gas: Least dense Liquid: Mid-level density Solid/Liquid: Definite volume
Which best describes why a liquid needs a container when a solid does not?
Solids have definite shapes, and liquids fill their containers.
___________ is the ability of one substance to dissolve in another.
Solubility
The substance that gets broken down in a homogeneous mixture is the _ .
Solute
A student is comparing two solutions. Solution A has a pH of 4 and solution B has a pH of 10. Which best describes the solutions?
Solution A is more acidic than solution B.
The same amount of substance was added to four beakers of water. The treatments were placed in the chart. Which best describes the solutions?
Solutions W and Y have greater solubility than solutions X and Z.
What happens when a substance undergoes a physical change?
Some physical properties change, but the substance keeps its identity.
_____ is the distance traveled during a specific unit of time.
Speed
__________ the distance traveled during a specific unit of time
Speed
It is written in equation form, p = mv, where p is momentum, m is mass in kg and v is velocity in m/s. Because momentum is a vector quantity, this means it has both magnitude and direction.
State in your own words the formula for momentum
Rutherford
States the nucleus is a small dense center of the atom, the nucleus has a positive charge, atom is mostly empty space (Gold Foil)
Kichi made a table to identify where she might find acids and bases in her house based on their common uses. What error did Kichi make?
Sulfuric acid would be found in the garage because it is used in car batteries.
Action and reaction forces are described by Newton's ________ law of motion.
THIRD
If voltage in a circuit is constant, the current can be cut to half of its original value by changing the resistance to _____ its original value.
TWO TIMES
The chart shows the solubility of different substances. Which statement is represented by the graph?
Temperature can change the solubility of a solute.
The equation below shows a general equation for a reaction, and the amounts of the substance are written underneath. AB + CD → AC + BD (15 g) (?) (?) (10 g) The total mass of the products is 50g. Which best completes the other two amounts?
The amount of CD is 35 g, and the amount of AC is 40 g.
Gerry is looking at salt under a powerful microscope and notices a crystalline structure. What can be known about the salt sample that Gerry is looking at?
The atoms are vibrating in place.
When the train moves with constant velocity how does a line on the graph appear?
The line continues to the right but it is horizontal with a slope equal to zero
When the train leaves the station, its speed is increasing over time. How would this look on a graph?
The line on the graph plotting this slopes up and to the right
Julie takes a cold glass of clear, colorless liquid out of the refrigerator and puts it on the table. As the liquid warms up to room temperature, Julie sees bubbles of gas form in the liquid and rise to the surface. Which conclusion is best supported by Julie's observations?
The liquid is a mixture because it has a gas dissolved in a liquid.
Which best describes the law of conservation of mass?
The mass of the reactants and products is equal and is not dependent on the physical state of the substances.
Maria examines a mixture that appears to be the same throughout. However, when she looks at a sample using a magnifying lens, she can see small droplets of liquid surrounded by another liquid. Which conclusion best fits her observations?
The mixture is a colloid because two different substances can be seen in a small sample.
the image below shows a method of separating a mixture that is made up of a volatile liquid that is dissolved in a less-volatile liquid. mc023-1.jpg Which process most likely takes place in this apparatus?
The mixture is heated, causing the solute to move from flask A to flask B.
What information on the periodic table is used to complete electron dot diagrams?
The number before the A at the top of a column shows how many dots to draw in the diagram.
Which statement best describes balancing equations and the law of conservation of mass?
The number of atoms is the same in the reactants and in the products, and the total mass is the same in the reactants and in the products.
Which can occur in a physical change?
The particles can arrange in different ways.
A bowling ball collides with a pin and pushes the pin toward the right. Which describes the reaction force
The pin pushes the bowling ball toward the left
Deceleration
The rate at which velocity decreases
Acceleration
The rate at which velocity increases
Acceleration
The rate of change of velocity with respect to time.
Which clue can be used to identify a chemical reaction as a decomposition reaction?
The reaction has a single reactant.
Which clue can be used to identify a chemical reaction as a double replacement reaction?
The reaction has two reactants with ions that seem to switch places.
Which clue can be used to identify a chemical reaction as a replacement reaction?
The reaction has two reactants with ions that seem to switch places.
The chart lists the masses of four balls that have the same momentum. Which correctly compares two of the balls?
The red ball has a greater velocity than the purple ball
A cannonball is launched from a cannon. The CHANGE IN MOMENTUM on the cannon compared to the cannonball is
The same
A cannonball is launched from a cannon. The FORCE on the cannon compared to the cannonball is
The same
A cannonball is launched from a cannon. The IMPULSE on the cannon compared to the cannonball is
The same
If you crash into a wall or driver into an identical car driving at the same speed, what would cause more damage
The same amount of damage would occur
Wax melts when it is heated. Which most likely describes what is true of the result of this reaction?
The same amount of wax exists before and after the change.
Suna passes an electric current through a sample of clear, colorless, and odorless liquid. As the experiment continues, bubbles form, and the volume of liquid decreases. Suna collects samples of two colorless, odorless gases that bubble out of the liquid. One of the gases burns. Neither the original liquid nor the other gas burns. Which is the best explanation of her results?
The sample was broken down by the electric current and formed a new substance that could burn. Therefore, the original liquid is a compound.
The pH of a solution is 7. Which best describes the solution?
The solution has the same number of hydrogen ions and hydroxide ions.
Carlotta adds too much salt to her soup. She recalls that evaporation can be used to separate salt from salt water, so she plans to leave the soup on the stove on low heat until the soup is less salty. Which will most likely happen to her soup?
The soup will become saltier because evaporation removes the water and leaves the salt behind.
Omar observes that many buildings in his city were built using limestone. He has read that acid rain can damage limestone. He also knows that limestone reacts with acids and that chemical reactions are affected by temperature. With this in mind, he conducts an investigation to see how the amount of damage to the limestone is affected by the amount of acid on the stone. Which statement describes the correct plan for his procedure?
The temperature, the type of limestone, and the type of acid are controls. The amount of acid and the amount of damage to the limestone are variables.
Democritus
Theorized that atoms are completely solid, atoms are different in their size, shapes and weight
While looking at bromine (Br) on the periodic table, a student needs to find another element with very similar chemical properties but with a different atomic mass. Which best describes the student's options?
There are many possible elements, and they are all in the same vertical column as bromine.
Read the passage about the fluoridation of drinking water. Since the early 1960s, fluoride has been added to many sources of drinking water to prevent cavities in teeth. This is called fluoridation. There are some who say that this is unnecessary and increases the risk of cancer. In 1993, the Subcommittee on Health Effects of Ingested Fluoride of the National Research Council, part of the National Academy of Sciences, conducted an extensive study about the link between fluoridated drinking water and increased cancer risk. The study included data from more than 50 human disease studies and six animal studies. The Subcommittee concluded that none of the data showed a link between fluoridated drinking water and cancer. A 1999 report by the CDC supported these findings. The CDC report concluded that studies so far have produced "no credible evidence" of a link between fluoridated drinking water and an increased risk for cancer. According to the article, what valid claim came from the National Research Council?
There is no link between fluoride exposure and increased cancer risk in humans.
Which statements best describe the atoms of the gas neon? Check all that apply.
They move at high speeds. They move freely in all directions. They move constantly. They are far apart.
Which best describes why scientists need to be creative?
They need to think of ways to solve problems.
Why is it important to have a control group in an experimental investigation?
To compare the results when the independent variable is not involved
the number of valence electrons it has
What does the group number indicate about the element?
The acceleration of an object as produced by a net force is directly proportional to the magnitude of the net force, in the same direction as the net force, and inversely proportional to the mass of the object.
What equation states Newton's second law of motion?
Constant value. Momentum does not increase or decrease
What is a necessary condition for the conservation of momentum?
Pablo wants to enter the science fair. Which question could be answered through scientific investigation?
What is the best angle to throw a ball for maximum distance?
After watching a show about submarines, Jamil wants to learn more about the oceans. Which question could be answered through scientific investigation?
What substances dissolve in ocean water?
Which describes a scenario that would most likely use an inhibitor?
When at rest, the body stores sugar.
Which had more momentum, a worm crawling across the road or a car parked on the road?
Worm
The pictures represent three different states of matter. Which order of pictures places molecules with the most amount of motion to the least amount of motion?
Y → Z → X
Jerome is learning how the model of the atom has changed over time as new evidence was gathered. He has images of four models of the atom, but they are not in the correct order. In what order should Jerome put these models to show the development from the earliest model of the atom to the most recent one?
Y, X, Z, W
hypothesis
a possible explanation of or answer to a scientific question that is based on prior knowledge or research and is testable
science
a process that involves the collection of information and ideas supported by evidence
Jenna took an open bowl of leftover mashed potatoes from the refrigerator. She determined that chemical changes occurred since the potatoes were first placed there. Which observations most likely led to Jenna's conclusion?
a production of odor
In a recent survey of students who graduated from a large public high school, nine out of ten students reported that they passed biology with a grade of seventy-five percent or higher. What further data could be produced to be sure that this information is accurate?
a review of the students' school transcripts
Hana fills a cup with sandy ocean water. She pours the mixture through a filter. What does she collect that passes through the filter?
a solution of salt in water
Which acid is a strong electrolyte?
a. sulfuric acid
A car suddenly stops going from 25 m/s to 0 m/s in 4 seconds. What is its acceleration?
a= -6.25 m/s2
Which would be least likely to completely dissolve in water?
acetic acid
A non-metal oxide reacting with water will synthesize a(n):
acid
Bleach should never be mixed with ammonia or with
acid.
Why do action/reaction forces NOT cancel each other out?
action and reaction forces are applied to different objects
The pH of an acid and base mixed together in solution depends on the
amounts of acid and base used.
When a solution of an acid reacts with a solution of a base, the pH of the resulting solution depends on the
amounts of acid and base used.
Soap can remove grease and oil from your skin because it acts as
an emulsifier to surround oil.
In addition to changing the symbol to C, how would this diagram compare with an electron dot diagram of a carbon atom (C)?
b. The same number of dots would appear in the diagram for carbon.
Which acid-base reaction will yield an acidic solution?
b. HNO₃ and NH₃
Which statement about bases is incorrect?
b. contain hydronium ions
Which phrase is not true about strong bases?
b. have pH ranges from 1 to 7
Tijuan mixed a solid and a liquid together in a beaker. He determined that a chemical change occurred. If his conclusion is correct, which substances could he have been observing and why?
baking soda mixed into vinegar, because the production of bubbles indicates that a new substance formed
objective
based on fact rather than opinion
subjective
based on opinion rather than fact
Crude oil is a mixture of many liquids. The crude oil enters the bottom of a tall column, where the mixture is heated. The substances rise up the column until they cool down and condense back to liquids. The components of crude oil can be separated because of differences in which property?
boiling point
in order to be scientific, evidence must be
both relatable and objective
In order to be considered scientific, evidence must be what two things?
both repeatable and objective
Jack is making a table to summarize his notes about the different types of scientific investigations. He places an X into the table to match the investigation type with the step. Part of the table is shown.
box 3
Fred has a large piece of sugar that is not dissolving in his drink. How could he get the sugar chunk to dissolve faster?
by breaking it up into smaller pieces
Akia is balancing the equation Na + H2O NaOH + H2. He tries to find the coefficients that will balance the equation. How could he find the correct coefficients?
by counting up each individual atom and make sure the atom numbers are the same in the reactants and the products
What is the most likely way in which an atom of magnesium (Mg) will satisfy the octet rule when it forms bonds?
by losing two electrons
Which is one way that scientists ensure that data is reliable?
by replicating experiments
Eddie stated the picture shows potential energy being transformed to kinetic energy. Val stated that it shows chemical energy being transformed to mechanical energy. Which best explains who is correct?
c. Both Eddie and Val are correct because chemical energy is a type of potential energy and mechanical energy includes kinetic energy.
Which material is the least likely to be recognized as a mixture by looking at it under a microscope?
c. a homogeneous mixture
How many electrons are shared between one nitrogen atom and one carbon atom?
c. 6
Which acid-base reaction will yield a basic solution?
c. CH₃COOH and NaOH
Which equation shows a strong acid dissolving in water?
c. HNO₃ + H₂O → H₃O⁺ +
Which of the following is not a use for household bleach?
c. to neutralize stomach acid
A student is trying to determine if a solution is acidic or basic. She does not have any litmus paper. Which would she most likely use to get a reading on her solution?
cabbage juice
While playing soccer, Carla slides across one of the lines on the field. When she stands up, what base does she dust off?
calcium hydroxide
What are the products of the combustion of a hydrocarbon?
carbon dioxide and water
Giant cave systems have formed through the reaction of acids with the that make up limestone.
carbonates
the unit of length that most nearly matches the width of your finger
centimeter
Making a pancake from batter is an example of a ________ change
chemical
A spacecraft is launched from Earth toward the moon. Where will the spacecraft be when the gravitational forces acting on it are equal?
closer to Earth than to the moon because Earth has greater mass than the moon
A spacecraft is launched from Earth toward the moon. Where will the spacecraft be when the gravitational forces acting on it are equal?
closer to the moon than to Earth because Earth has greater mass than the moon
Charlie is balancing an equation. She has identified the atoms and counted the number of each in the reactants and products. What would Charlie adjust to make the number of atoms in the reactants the same as the number of atoms in the products?
coefficients
Polyatomic ions bond with other ions to form ionic ______.
compounds
There are a few ways to increase the rate of a reaction. When the amount of a substance in a given volume is increased, this is altering the _____.
concentration
A baseline for an experimental investigation is provided by the________
control group .
Which serves as evidence for a scientific claim?
controlled experiments
A magnifying glass will create a larger, virtual image because the glass is made of a ___ lens.
convex
A scientist who solves a new problem using something already learned is being _________
creative
Which of the following is a basic compound?
d. All of the above
Which part of a soap dissolves in water?
d. All of the above
Which is an example of a neutralization reaction?
d. H₃O⁺ + OH → 2H₂O
Which household substance is a base?
d. None of the above
Which solution is the most acidic?
d. a solution with a pH = 1
Which of the following substances is a base?
d. bleach
what isnt a unit for speed?
d/t
A recipe gives the instructions below. After browning the meat, pour off the fat from the pan. To further reduce fat, use a strainer. What type of separation methods are described in the recipe?
decantation and screening
the term that best describes the motion of an object slowing down
deceleration
Actinobacteria sp. are fermenting organisms (which do not use oxygen to breathe) referred to as chemoorganohetereotrophs. This means they break down organic material and convert it to inorganic material. Which part of the carbon cycle does this describe?
decomposition
Which process plays an important role in the biogeochemical cycles of carbon, nitrogen, and phosphorus?
decomposition
Thiobacillus denitrificans is a species of bacteria that obtains its energy from carbon dioxide and inorganic compounds such as nitrogen in its environment. It is used in bioremediation (natural cleansing) of groundwater that contains excess nitrate, allowing the nitrates to be removed. How does Thiobacillus denitrificans help bioremediate groundwater?
denitrification
Rahul sees a flock of birds. He watches as the flying birds land in neat little rows on several power lines. Which change of state does the motion of the birds most closely model?
deposition
The process by which a gas changes to a solid is
desposition
An advertisement for a new fish food claims that lab studies show that fish grew three inches in three weeks while eating the food. Travis wondered if the food was worth the extra cost.
determine if the results show the independent variable changing as the dependent variable was changed.
Acceleration involves a change in speed and
direction.
in a motion experiment with a car on a track, the car moves 50 cm away from the origin, then moves 20 cm towards the origin. whats the cars displacement and distance traveled
displacement equals 30 cm and distance equals 70 cm
Speed is calculated by taking _ divided by time.
distance
Speed is calculated by taking _______ divided by time.
distance
Which could describe the motion of an object? Check all that apply.
distance = 0 and displacement = 0 distance = 10 meters and displacement = 0 distance = 10 meters and displacement = 10 meters distance = 10 meters and displacement = 1 meter
Linh is analyzing a solution in a crime lab. He needs to determine what liquid was used to dissolve the other substances. Which method would best complete the task?
distillation
if you know the distance to traveled and the amount of time it took, speed may be calculated by
dividing distance by time
the slope of the line of a graph is calculated by
dividing the change in the vertical values by the change in the horizontal values
An ionic bond forms between sodium and chlorine when the sodium atoms electrons.
donate
Which product contains a strong base that would most likely completely dissolve in water?
drain cleaner
The subatomic particle that has the least mass is the
electron
The water in a 150-mL flask is poured into a beaker that contains 600 mL of ethyl alcohol. Which substance is the solvent in this mixture
ethyl alcohol because it has a much larger volume than water
Which process allows water to enter the atmosphere?
evaporation
Which separation method would be most successful in separating the components of a homogeneous mixture?
evaporation
A firework being ignited is an example of a(n) _____ reaction.
exothermic
a carefully designed test done under controlled conditions
experiment
Which is a common characteristic of both science and pseudoscience?
experimentation
what net force is requiered to accelerate a 10 kg wagon by 4 m/s2
f=40n
why are SI units used so often in science?
factors of 10 are easier to work with mathematically
Metals always retain their charges in a single replacement reaction
false
Which method of separating a mixture involves passing a heterogeneous mixture through several layers of different materials?
filtration
the equation that correctly expresses newtons second law
force=mass*acceleration (f=ma)
Hamid made this table to organize his notes on the properties of acids and bases. Which property is in the wrong column?
form hydrogen gas with metals
When an object is accelerating due to the force of gravity with no other forces acting on it, it is in___________
free fall
Michael has a substance that he puts in Container 1. The substance has a volume of 5 cubic meters. He then puts the substance in Container 2, and it now has a volume of 10 cubic meters. In which phase(s) is the substance?
gas
Density describes how much mass is contained in a certain volume. Knowing how far apart molecules are in each state, which best ranks solids, liquids, and gasses from least dense to most dense?
gas < liquid < solid
The only force that can act on an object in free fall is
gravity
Read the claim. Breakfast is an important meal. It jump starts the body's process of using calories to break down food. Appetite can decrease with age, but going too long without eating causes metabolism to slow down. Current research shows that incorporating legumes such as lentils and chickpeas into meals boosts metabolism for twenty-four hours. Who might benefit from this claim?
grocery stores that sell legumes
In a single replacement reaction, diatomic chlorine displaces iodide in an ionic compound. This is a:
halide-halide replacement
Which characteristic(s) makes ionic compounds useful as a building material?
hardness and brittleness
Atoms of which elements form bonds without satisfying the octet rule?
helium (He) and hydrogen (H)
All large radioactive atoms decay into smaller atoms by releasing alpha particles. Each alpha particle has 2 protons, 2 neutrons, and 0 electrons. The table below describes several neutral, low-mass atoms. An alpha particle is also referred to as a nucleus of which isotope?
helium-4
Which two characteristics of data always occur together?
high precision and good validity
Maya tried to hit four golf balls into a hole marked with a flag. The diagram shows where the golf balls landed. Which best describes Maya's results?
high precision, low accuracy
Which clue can be used to identify a chemical reaction as a combustion reaction?
hydrocarbon reacts with oxygen.
When an old building is to be torn down, Mr. Pham's company removes the bricks, cleans off the mortar from the bricks, and then sells the bricks to companies that restore historic buildings. Which compound is Mr. Pham's company most likely to use in its work?
hydrochloric acid
Which substance is used to remove rust from metal?
hydrochloric acid (HCl)
What ion do acids release in solution?
hydrogen
is the only element in group 1 on the periodic table that forms covalent bonds.
hydrogen
Which elements do hydrogen fuel cells combine to produce electricity?
hydrogen and oxygen
The pH of a substance is a measure of its
hydronium ion concentration.
What ion is most closely associated with bases?
hydroxide
Sebastian wants to write the chemical formula for phosphorus tetraoxide. Which steps will he take at some point in his process? Check all that apply.
identify the elements involved as potassium and oxygen identify the symbols as P and O add a subscript of 4 after the O
Jack is making a table to summarize his notes about the different types of scientific investigations. He places an X into the table to match the investigation type with the step. Part of the table is shown. Where should Jack place an X?
in Box 1
Keisha is making a table summarizing her notes about the different types of investigation. She places an X into the table to show which steps are included in a descriptive investigation. Part of the table is shown. Where should Keisha place an X?
in Box 1 only
when an object is accelerating due to the force of gravity with no other forces acting on it, it is ____
in free fall
Which of these factors will cause a solid solute to dissolve faster?
increasing the surface area of solute
the variable usually represented on the x-axis of a graph is the ~what~ variable?
independent
Nami conducts an investigation on plants. She places a grow light on a timer to give the plants different amounts of light to see if this would affect their growth. In this investigation, the amount of light is the___________-
independent Variable
An object's resistance to any change in its motion is the of ---------the object.
inertia
Gerard lives in a tropical region where the average annual temperature is 77°F and the average annual rainfall is more than 100 inches a year. He surveys 25 people in his neighborhood about items they regularly use and records the data into a table. http://media.edgenuity.com/evresources/3208/3208-01/3208-01-07/3208-01-07-assessment/3208-01-07-01.png For which products has Gerard most likely recorded the data with an error?
insulated gloves
Soaps and detergents are
ionic compounds.
Different of an element have different numbers of electrons.
ions
Which characteristic of a substance is considered a chemical property?
its reactivity
A disinfectant is a substance that
kills bacteria and viruses.
An electric motor converts electrical energy into _____ energy
kinetic
As the speed of an object doubles, what happens to the kinetic energy?
kinetic energy increases as the square of speed. Ex. Speed increases 2x so kinetic energy increases 2x2 (4x)
Which solution has the greatest number of hydrogen ions?
lemon juice, pH = 2
Which units are used to measure both velocity and speed? Check all that apply.
m/s km/h mph
What are the units used for acceleration?
m/s2
units of measurement used it label a quantity of acceleration
m/s^2
units of measurement used to label a quantity of accelerations are
m/s^2
you push a box with a force of 35 N and the box accelerates at 3.5 m/s2
m=10kg
force is a vector that has both_______ and direction.
magnitude
A cathode ray tube is made of glass with a small amount of some kind of gas in it. It has metal electrodes at each end to pick up pick up an electric current. The electrodes are named "positive" and "negative," which were words used by Benjamin Franklin in the 1700s to describe electricity. A bright ray forms in the gas when an electric current is applied to metal electrodes. In the 1800s, an important scientist suspected that the negatively charged particles in a cathode ray were present in all atoms. What procedure would allow that scientist to investigate this idea?
making cathode ray tubes out of different materials to see if the ray is the same
While researching life during colonial times, Carson learns that people would extract potassium hydroxide from wood ashes and mix it with animal fat. What were the colonists doing?
making soap
Even though it is the same ________________ as a proton it is electricity neutral, hence the name neutron.
mass
Which factors affect the gravitational force between two objects?
mass and distance
the inertia of an object is related to its
mass only
According to Newton's second law of motion, what is force equal to?
mass times acceleration
The atomic symbol mc025-1.jpg represents potassium-40 (K-40), a radioactive isotope that has 19 protons and 21 neutrons. Which atomic symbol could represent an isotope that results from the decay of K-40?
mc025-2.jpg
The ratio of output force to input force is the ___ of a machine.
mechanical advantage
Frieda makes a pyramid of oranges for a display at the grocery store. A few minutes later, Corwin bumps into the display and the oranges spill down. Which change of state does the motion of the oranges most closely model?
melting
The process by which a solid changes to a liquid is
melting
Which would show an example of how physical changes are reversible?
melting tin and then cooling it into a mold
The diagram shows the moon and Earth in space. Which is the best label for the dotted-line arrow?
moon's motion without gravity
Which would increase the rate of dissolving? Check all that apply.
more surface area high temperature a lot of agitation
The density of solid aluminum is 2.70 . If a 1g peice of aluminum is dropped in a cup of water, it will . (The density of water is 1.00 g/cm3 )
n/a
An acid or a base dissolved in water breaks down into a positive and a _____ ion.
negative
the si unit of force preferred by scientists is the
newton
is colliding bodies sticking to one another an inelastic collision
no
Which best describes Earth's magnetic field lines?
not c. The field lines go out of Earth in northern Canada, enter Earth near Antarctica, and are aligned with the geographic poles.
acceleration if an object must be caused by a force that is
not zero
The elements in group 17 of the periodic table are all called halogens. All halogens have the same
number of valence electrons.
All atoms of a single element have the same ___________ of ______________.
number; protons
Jenna took an open bowl of leftover mashed potatoes from the refrigerator. She determined that chemical changes occurred since the potatoes were first placed there.Which observations most likely led to Jenna's conclusion?
odor
Justin is making a snack. He toasts a piece of bread and spreads peanut butter and jelly on it. Then he cuts an apple into several slices and adds these to his plate. Next, Justin mixes a scoop of lemonade powder into a glass of water, mixes it, and adds ice.
one
Justin is making a snack. He toasts a piece of bread and spreads peanut butter and jelly on it. Then he cuts an apple into several slices and adds these to his plate. Next, Justin mixes a scoop of lemonade powder into a glass of water, mixes it, and adds ice. How many chemical changes occurred in this scenario?
one
Two people push on the same door from opposite sides as shown.
one person exerts more force than the other so that the forces are unbalanced.
Two people push on the same door from opposite sides as shown. They will only see the door move when
one person exerts more force than the other so that the forces are unbalanced.
Which ranks these materials by the attraction between their atoms from the weakest to the strongest?
oxygen gas, liquid water, liquid honey, solid iron ore
A 0.3 kg baseball thrown at a speed of 35 m/s, and a 8 kg bowling ball rolling at 3 m/s are both stopped in 0.5 seconds. Which ball is stopped with MORE force because it has MORE momentum?
p2 = 24 kg.m/s
The ______ is a measure of how acidic or basic a solution is.
pH
What happens to the pH of the acid in your stomach when you take an antacid?
pH increases
What is it called when scientists in the same or similar field of study judge the quality of a fellow scientist's scientific claim?
peer review
Chou is curious about the effect of magnets on how plants grow. He sets up ten pots with alfalfa sprouts. He places strong magnets under five of the pots but does not put magnets under the other five pots. This is an example of which scientific practice?
performing an investigation
Which products rely on the ability of ionic compounds to conduct electricity? Check all that apply.
phones, toys
Osteoporosis is a disease that affects the bones and leads to an increase in bone fractures. Osteoporosis is most likely to be affected by which cycle?
phosphorus
A ________ property is a characteristic of a substance that can be observed and does not change the identity of the substance.
physical
A physical science teacher calculates each student's final grades by using the weighted rubric below. Which type of graph is best suited to show the breakdown of how this teacher weighs each category?
pie graph
When converting a number from scientific notation to standard notation, if the power of 10 is ____________, move the decimal place to the left.
positive
When an atom that has no charge loses two electrons, it becomes a
positive ion.
When sodium atoms (Na) and chlorine atoms (Cl) join to make sodium chloride, or table salt, they form an ionic bond. Using this information, which pair of elements is most likely to form an ionic bond?
potassium (K) and fluorine (F)
Which compounds are used in batteries? Check all that apply.
potassium hydroxide sulfuric acid
energy that is stored due to the position of an object may be called _____ energy
potential
Leslie wants to know which advertising medium works best to promote her electronics store. She surveys her customers over a weekend and creates a bar graph. Based on her survey, which advertising mediums will work best to publicize Leslie's in-store specials?
printed flyers and Internet
All atoms of the same element must have the same number of
protons
For the equation BaCl2 + Na2SO4 → BaSO4 + 2NaCl, how many chlorine atoms are on the reactants side and on the products side?
reactants: 2; products: 2
According to the law of reflection, the angle of incidence is equal to the angle of ____.
reflection
A(n) _______ is a material that causes a wave to bounce off of it.
reflector
If data are from a trusted source and the results are validated by multiple tests, the evidence supporting a scientific claim is
reliable
The law of conservation of momentum states that, if left alone, the total momentum of two interacting objects that make up a system .
remains the same
The model below shows a carbide ion. What could be done to change this carbide ion to a neutral carbon atom?
remove 4 electrons
A chemical reaction that has the general formula of AB + C → CB + A is best classified as a reaction.
replacement
When Coach Kwan notices that a player is getting tired, she takes out the tired player and substitutes a fresh player. Which type of chemical reaction does this best model?
replacement
Which type of reaction has the general formula of AB + CD → AD + CB?
replacement
Which type of reaction is NaCl + AgNO3 → NaNO3 + AgCl?
replacement
A scientist conducted an experiment and discovered that certain plants grow faster when given a particular amount of fertilizer. Another scientist conducted the same experiment and got similar results.
replication
The ocean and the atmosphere serve as long-term storage areas for carbon and other nutrients. What are these storage areas called?
reservoirs
In metals, the properties of malleability and ductility are explained by the fact that metallic atoms can
roll over without breaking their bonds.
Positive ions from a base and negative ions from an acid form a _____ .
salt
Which solution is a homogeneous mixture?
salt and water
Mariyam, a marine biologist, measures the length of a great white shark at 4.5 m long and its teeth at an average of 50 mm long. She wants to convert both measurements to centimeters.
shark length: 450 cm; teeth: 5.0 cm
Because of metallic bonding, when light is pointed at metals, they become
shiny
what term in used to describe the meaningful digits in a measurement?
significant
Some isotopes of elements are unstable and decay into other, more stable isotopes over time. For example, it takes 153 years for half of a sample of silicon (Si) atoms with 14 protons, 14 electrons, and 18 neutrons to decay. What is the name of this specific silicon isotope?
silicon-32
Soap-making is a reaction between compounds found in animal fats or vegetable oils and
sodium hydroxide or potassium hydroxide.
Atoms in a stay in a fixed position and have no freedom to move.
solid
The substance that gets broken down in a homogeneous mixture is the_____
solute
A beam of light passes though a liquid in a test tube without scattering. Which type of mixture is most likely in the test tube?
solution
Which lists mixtures, in order, from the smallest particles to the largest particles?
solution, colloid, suspension
observation
something that is recognized or noticed using the senses
If forces acting on an object are unbalanced, the object could experience a change in ____ , direction, or both.
speed
If forces acting on an object are unbalanced, the object could experience a change in _________ , direction, or both.
speed
Which data can be measured quantitatively
speed of light
Which data can be measured quantitatively?
speed of light
An object in projectile motion will follow which path?
straight down toward the ground
The label on a bottle indicates that the substance inside has a pH of 13. This tells you that the substance is
strongly basic.
During which change of state would the volume of a substance increase the most?
sublimation
During which changes of state do atoms that cannot move past one another become free to move?
sublimation and melting
Which atom is most likely to accept electrons to form an ionic bond?
sulfur, a nonmetal with 6 valence electrons
A _____ solution is a heated solution that holds more dissolved solution than it can hold at a lower temperature.
supersaturated
A product that is a chemically bonded combination of reactants will form in which type of reaction?
synthesis
When explaining chemical reactions to a friend, Brianna models a reaction by taking several colors of modeling clay and making a sculpture of a horse. Which type of chemical reaction is Brianna most likely explaining?
synthesis
Identify the reaction type for each generic chemical equation. A + B → AB: AB → A + B: Hydrocarbon + O2 → CO2 + H2O: AB + CD → AD + CB:
synthesis decomposition combustion replacement
When someone throws a ball, the action force is the person pushing on the ball. What is the reaction force?
the ball pushing on the person
while standing on a stationary skateboard, Jolene tosses a heavy ball horizontally towards one end of her skateboard. The skateboard moves. Assuming there is no friction in the system when the ball is tossed, which statement about the momentum of the heavy ball is incorrect?
the directions of the balls momentum and jolenes momentum are the same
terminal speed occurs when
the force of gravity is balanced by the air resistance of an object
What are the two parts of an atom?
the nucleus and the electron cloud
The diagram shows organisms a diver observed during an ocean dive. What did the diver most likely use as a reference point to describe the position of the squid?
the ocean surface
The diagram shows organisms a diver observed during an ocean dive. What did the diver most likely use as a reference point to describe the position of the squid?
the ocean surface
kiki accidentally nudges a glass tumbler with her elbow and it falls toward a hard, ceramic tile floor. as a soccer player, Kiki reacts by catching the class with her foot and lowering it to the floor, preventing the glass from breaking. Her action prevents the breakage because:
the time interval for stopping is greater when kiki catches the class with her foot
Lidia plans an experimental investigation to see how the thickness of a lens affects the point where a beam of light is focused. She plans to shine light through a lens and measure the distance to a screen that is placed where the beam focuses.
the type of light and the material of the lens
Lidia plans an experimental investigation to see how the thickness of a lens affects the point where a beam of light is focused. She plans to shine light through a lens and measure the distance to a screen that is placed where the beam focuses. What are the controls in Lidia's investigation?
the type of light and the material of the lens
Describe the relationship between "Impulse" and "Change in Momentum".
they are measuring the same thing
The first model of the atom was developed through
thinking about the smallest particles of matter without experimenting.
Action and reaction forces are described by Newton's ____law of motion.
third
Davahl is interested in tortoises because they can live for over a hundred years and have unique metabolisms. She wants to perform an experiment to see if they can live even longer with a specific nutrient supplement. Davahl is given a five-year research grant to perform her experiment. Which is the most likely practical limitation that Davahl is having with performing her experiment?
time
If you divide distance by speed, what are you calculating?
time
Micah knows that a car had a change in velocity of 15 m/s. To determine acceleration, Micah also needs the of the total trip in seconds.
time
Work can ____ energy between objects and can cause a change in the form of energy.
transfer
When mixed, which states of matter form only a homogeneous mixture?
two gases
Give an example of an Elastic collision.
two pod balls collide and bounce off eachother. No loss of energy
On a cool morning, Uyen's breath can form a cloud when she breathes out. Which changes of state are most responsible for Uyen seeing her breath in this way?
vaporization and condensation
when you throw a ball up in the air, it travels up and then stops instantaneously before falling back down. at the point where it stops and changes direction to fall back down its:
velocity is zero
calculate the work done to lift the barbell weighing 200 N a distance of 1.25 meters
w=250J
When a solution of an acid reacts with a solution of a base, hydronium ions react with hydroxide ions to form
water.
According to Newton's first law of motion, when will an object at rest begin to move?
when an unbalanced force acts upon it
When does a skydiver achieve terminal velocity?
when gravity equals air resistance
Elements in group 2 are all called alkaline earth metals. What is most similar about the alkaline earth metals?
which chemical properties they have
Students are completing a table about a particular subatomic particle that helps make up an atom. What best explains how they should complete the table?
with "Outside of the nucleus," because the particle is an electron
It takes a runner 3 seconds to accelerate to a speed of 6 m/s near the finish line of a race. If his acceleration is 1.5m/s 2 , what was his initial velocity?
x=1.5
Which formulas might be used to find the velocity based on a position-time graph? Check all that apply.
y2 - y1 x2 - x1 y2 - y1/x2 - x1
you raise a penny per meter walked by you in a fundraiser. you walk 15 km. how much money do you raise?
$150.00
Scientists are working with a liquid that is made of only one type of atom. Which statements correctly describe this liquid?Check all that apply.
- The liquid contains only one element. -The liquid is a pure substance.
Polly is pushing a box across the floor with a force of 30 N. The force of gravity is -8 N, and the normal force is 8 N. Which value could describe the force of friction if Polly could not move the box?
-30 N
A tugboat is pushing a barge into a harbor. The barge is exerting a force of 3000 N against the tugboat. Which force would most likely allow the tugboat to move the barge into the harbor?
-4500 N
Which method would be best to separate a mixture of sugar and water?
-Distillation
In which changes of state do atoms lose energy? Check all that apply.
-Freezing -Deposition -Condensation
Based on the tug of war pictured below, what is the net force?
10 N
Which are reasons why hydrogen is considered a better fuel source for cars? Check all that apply.
-It is renewable. -It emits no harmful emissions. -It reduces dependency on petroleum. -It reduces air pollution.
The element phosphorus is located to the right of the element magnesium along the same period in the periodic table. Which best describes the relationship of the elements?
-Phosphorus has a larger atomic mass.
_ is the displacement of an object during a specific unit of time.
Velocity
Which method would be best to separate a mixture of sand and gravel?
-Screening
If forces acting on an object are unbalanced, which factors may result from an unbalanced force? Check all that apply.
-The net force is negative. -The net force is positive. -There is a change in motion
the amount if mechanical kinetic energy possessed by a 0.25-kilogram ball rolling at a speed of 2.5 meter per second is ______ joules
0.78
What is the pH of a 0.1 M solution of the strong acid HNO₃ in water?
1
The graph represents velocity over time. What is the acceleration?
0.2 m/s2
What is the mass of a neutron?
1 am
How many atoms of each element are in the chemical formula Ca(OH)2?
1 calcium, 2 oxygen, and 2 hydrogen
_________ is the displacement of an object during a specific unit of time.
Velocity
jonah is pushing his younger sister on a swing. if she weighs 35 kg, how much higher above the ground must Jonah push her to increase her potential energy by 525 Joules
1.5 meters
Which method would be best to separate a mixture of oil and water?
-separation of density
Distillation
-separation of the components of a mixture based on boiling points
Screening
-separation technique for dry heterogeneous mixtures based on particle size
Gwennen rides her bicycle 2.4 kilometers up a steep hill in 8 minutes her speed is how many km/min
0.3 km
When velocity is constant what does acceleration equal?
0
The diagram shows two balls before they collide. What is the momentum of the system after the collision?
0.2 kg m/s
The diagram shows two balls before they collide. What is the momentum of the system after the collision?
0.2 kg • m/s
The chart show the masses and velocities of two colliding objects that stick together after a collision. According to the law of conservation of momentum, the momentum of the object after the collision is ____ kg • m/s.
1,500
This is how osmium appears in the periodic table. Rounded to the nearest whole number, how many neutrons, on average, are in an atom of osmium?
114
If the mass of the products measured 120 g, what would be the mass of the reactants?
120 g
ken rolls a 7k bowling ball so slowly that it stops before it moves through all of the pins. the impulse necessary to stop this bowling ball rolling at 2 m/s is how many newton-seconds
14
Doug rides a motorcycle at an average speed of 42 mph for 3.6 hours. The distance he travels is about how many miles?
150 miles
The modern periodic table has __ groups. (Write your answer as a number.)
18
Koto is walking at a velocity of 4.5 m/s south. She started at her house and traveled 15000 meters north, 5000 meters east, 20000 meters south, and then 5000 meters west. What is her time based on her velocity? (There are 60 seconds in 1 minute.)
18.5 minutes
A bungee jumper falls off a tower and it takes 2 seconds for her bungee cord to pull her back up. What was her velocity in free fall after 2 seconds?(gravity * time)
19.26 m/s
What is the pH of a 0.01 M solution of the strong acid HNO₃ in water?
2
What is the subscript for nitrogen in hydrazine, N2H4?
2
How many atoms of each element are in the chemical formula NH4NO3?
2 nitrogen, 4 hydrogen, and 3 oxygen
Recoil
2 objects start together and then move apart
What is the mass of a crate if a force of 200 N causes it to accelerate at 8 m/s2? (Formula: F=ma)
25 kg
What products should she record in the last row of the table?
2LiCl + 3O2
Lars is balancing equations with his study group. He is unsure about one equation because each member of the study group came up with a different answer. Which is the proper way to balance the equation Ca(OH)2 + H3PO4 → Ca3(PO4)2 + H2O?
3Ca(OH)2 + 2H3PO4 → Ca3(PO4)2 + 6H2O
Two carts collide and bounce apart. Cart 1 had a momentum of -6 kg • m/s before the collision. Cart 2 had a momentum of 10 kg • m/s before the collision. What is the total momentum of the carts after the collision?
4 kg • m/s
6.0 mega grams is equivalent to
6,000 kilograms
A solution that is mildly acidic would have a pH of approximately
6.
What is the momentum of a 5 kg object that has a velocity of 1.2 m/s?
6.0 kg m/s
What is 6.9 × 107 written in standard form?
69,000,000
The number of hydrogen ions would equal the number of hydroxide ions in a solution with a pH of
7
The number of hydrogen ions would equal the number of hydroxide ions in a solution with a pH of ___ .
7
The product side of a chemical reaction is shown. → 7Ti2(SO4)3 Which number represents a coefficient?
7
if a 40,000 kg rocket were traveling from its launch pad at a speed of 150 meters per seconds, 800 kilograms of gases would be expelled from the rocket at a speed of about:
7,500 m/s
A screw has 4 threads per centimeter and a circumference of 2 centimeters. The mechanical advantage of the screw is
8
Acceleration= (vf-vi)/t(14.0 m/s) / 8.0s= .50m/s^2
A bicycle takes 8.0 seconds to accelerate at a constant rate from rest to a speed of 4.0 m/s. If the mass of the bicycle and rider together is 85 kg, what is the net force acting on the bicycle?
Plants use sunlight as energy to convert carbon dioxide and water into glucose and oxygen. Which best describes the reaction?
A. The law of conservation of mass indicates the same amount of carbon will be found in the reactants as in the products.
Newton's first law of motion was a giant leap forward in scientific thought during Newton's time. Even today, the idea is sometimes difficult at first for people to understand. Which statement is the best example of an object and motion that would make it hard for people to believe Newton's first law?
A rolling ball eventually slows down and comes to a stop.
Which statement best describes a true solution?
A true solution will not separate in a centrifuge.
Newton's first law of motion was a giant leap forward in scientific thought during Newton's time. Even today, the idea is sometimes difficult at first for people to understand. Which statement is the best example of an object and motion that would make it hard for people to believe Newton's first law?
A. A rolling ball eventually slows down and comes to a stop.
What does the octet rule state that explains why atoms bond?
A. An atom bonds to have eight valence electrons to become stable.
A skydiver falls toward the ground at a constant velocity. Which statement best applies Newton's laws of motion to explain the skydiver's motion?
A. An upward force balances the downward force of gravity on the skydiver.
Which best explains how radiation is helpful in the plastics industry?
A. It makes plastics easier to shape.
You may be wondering why the action and reaction forces acting on the swimmer do not cancel each other and produce a net force of zero. The reason is that the action and reaction forces do not act on the same object. Only when equal and opposite forces act on the same object do they result in a net force of zero
Action-Reaction Forces Do Not Cancel
Can you determine the action and reaction pair between a swimmer and the water? Unlike the swimmer in the previous example, not all action and reaction forces produce motion
Action-Reaction Forces and Motion
Is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid.
Air Resistance
The equations are not balanced. Which equation would have the same coefficients in the same order as 2CO2 + 3H20 → C2H6O + 3O2?
Al + FeO → Al2O3 + Fe
The equations are not balanced. Which equations would have the same coefficients in the same order as 2CO2 + 3H20 → C2H6O + 3O2? Check all the apply.
Al + FeO → Al2O3 + Fe
Heterogeneous Mixtures
All of the separation techniques that will be discussed in this lesson center on the fact that one member of a mixture can be distinguished from the others based on its physical properties. For example, if you wanted to separate the tomatoes from the salad above, you could use their characteristic color (red), shape (round), and texture (smooth) to distinguish them; then you could just use your fingers to pick them out.
The table shows the relationship between the masses of two objects, the distance between the two objects, and the gravitational force between the objects. Which conclusion is supported by the data in the table?
An increase in the distance between the objects causes a greater change in the gravitational force than the same increase in mass.
Metal atoms tend to give away valence electrons when they bond with nonmetal atoms. What type of bond will form between the metal and nonmetal atoms and why does this bond form?
An ionic bond will form because electrons are transferred.
A skydiver falls toward the ground at a constant velocity. Which statement best applies Newton's laws of motion to explain the skydiver's motion?
An upward force balances the downward force of gravity on the skydiver.
This chart shows characteristics of three different types of atoms. Which statement is best supported by the information in the chart?
Atom Y will accept electrons from Atom Z
Oppositely charged objects attract each other. This attraction holds electrons in atoms and holds atoms to one another in many compounds. However, Ernest Rutherford's model of the atom failed to explain why electrons were not pulled into the atomic nucleus by this attraction. What change to the atomic model helped solve the problem seen in Rutherford's model?
Bohr's work with atomic spectra led him to say that the electrons were limited to existing in certain energy levels, like standing on the rungs of a ladder.
Which statement best compares and contrasts two physical properties of matter?
Boiling points and melting points are similar because they both involve the change in a state of a material, but they are different because boiling point involves a change from a liquid to a gas and melting point involves a change from a solid to a liquid.
Which best blocks X-ray particles and can therefore be observed more closely through the use of this technology?
Bones
Two objects bounce off each other.
Elastic collision: what it looks like
An atom of lithium (Li) forms an ionic bond with an atom of chlorine (Cl) to form lithium chloride. How are the valence electrons of these atoms rearranged to form this bond?
Electrons are transferred from the lithium atom to the chlorine atom.
The modern model of the atom describes electrons in a little less specific detail than earlier models did. Why is it that being less sure about the placement of electrons in an atom is actually an improvement over earlier models?
Electrons do not follow specific paths, so describing the area where an electron is likely to be is more scientifically accurate.
These models show the electron structures of two different nonmetal elements. Which element is likely more reactive, and why?
Element 2 is more reactive because it does not have a full valence shell, so it will attract electrons.
the measurement system used most commonly for everyday measurements in the US is the
English system
Newton's Third Law of Motion
Every action has an equal reaction
In an illustration, lines of force are drawn around a magnet to illustrate the magnetic ___.
FIELD
Jill is pushing a box across the floor. Which represents the upward force perpendicular to the floor?
FN
Julian stands on his toes to lift his body high enough so that he can reach a book. In this example, Julian's toes are a ______
FULCRUM
Why is the Metric system used in science instead of the English system?
Factors of ten are easier to work with mathematically
Free Fall
Falling with no resistance
Pressure is defined as force per unit area. It is usually more convenient to use pressure rather than force to describe the influences upon fluid behavior. The standard unit for pressure is the Pascal, which is a Newton per square meter. Friction also acts on a submarine moving through water and on an airplane flying through the air. Water and a mixture of gases such as air are known as fluids.
Fluid Force
Jill is pushing a box across the floor. Which represents the upward force perpendicular to the floor?
Fn
Maggie is a member of her school's environmental club and is interested in recycling. She asks the question, "How does exposure to the environment affect recyclable plastics?" What best describes why and how Maggie should change her question to make it a better scientific question?
Focus
The chart shows the time, initial velocity, and final velocity of three riders. Which best describes the riders?
Gabriella is slowing down at the same rate that Kendall is speeding up, and Franklin is not accelerating.
Galileo studied motion by rolling balls down wooden ramps. He studied how gravity produces constant acceleration. Galileo concluded that moving objects not subjected to friction or any other force would continue to move indefinitely
Galileo (1564 - 1642)
The chart indicates the time, speed, and velocity of five runners. Which best describes the runners?
Garreth and Elisa ran together, Luigi and Jasmine went the same distance, and Logan and Jasmine have the same displacement in the opposite direction.
Henry mixed salt and water together in a cup until he observed a clear solution. He measured the mass of the solution. Then he placed the cup outside for several sunny days during the summer. After a week, he observed that only solid salt remained in the cup and the mass had decreased. Henry concluded that a physical and chemical change occurred in this investigation. Which statements correctly defend or dispute his conclusion?
He is incorrect. Dissolving salt in water and evaporation of the water are both physical changes. The reappearance of salt is evidence that the change was reversible by a physical change, so it could not be a chemical change.
Sal drew the electron dot diagram of an aluminum atom as shown. How should Sal correct his diagram?
He should add a single dot below the symbol.
Hector drew the diagram below to illustrate projectile motion. How should Hector correct his diagram?
He should make the arrow for "Path" curve downward.
Lila is a track and field athlete. She has to complete four laps around the track, which is 400 meters. The race took her 6 minutes to complete. Which best describes her speed and velocity?
Her speed is 4.4 m/s, and her velocity is 0 m/s.
Why did Thomson's results from experimenting with cathode rays cause a big change in scientific thought about atoms?
His results gave the first evidence that atoms were made up of smaller particles.
Kai was 200 meters north from his house when he remembered he had to take some books to the library. It took him 200 seconds to do the round trip. Which best describes Kai's roundtrip?
His speed was 2 m/s, and his velocity was 0.
Kai was 200 meters north from his house when he remembered he had to take some books to the library. It took him 200 seconds to do the round trip. Which best describes Kai's roundtrip?
His speed was 2m/s, and his velocity was 0
Change in momentum: term only
Impulse: definition
Maria works in a hardware store. A bin of aluminum nails and a bin of iron nails are knocked over, and the nails get mixed up. Both sets of nails are the same color and size. What makes separating the nails a fairly easy job?
Iron is magnetic, and aluminum is non-magnetic.
The word "cumulative" means that something builds on itself. Which example best shows how scientific knowledge is cumulative?
Kepler based his laws of planetary motions off of Newton's law of gravity.
The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance gain energy during a change of state. Before the change, the atoms are close together and cannot slide past one another. After the change, the substance can fill its container. Which arrow represents the change of state described above?
L
Which two chemists organized elements based on properties such as how the elements react or whether they are solid or liquid?
Lavoisier and Döbereiner
the law that states that energy cannot be created or destroyed but can be changed from one form to another
Law of Conservation of Momentum
Newton's First Law of Motion
Law of inertia
The atoms in a sample are close together but can slide past one another. As the atoms lose energy, they move slower. The atoms become locked in place because of attractive forces between them. Which change of state is taking place?
Liquid to Solid
While developing his periodic table, Dmitri Mendeleev broke his own rule and placed the element tellurium before iodine in the group. He did this even though tellurium's atomic mass was known to be greater than iodine's. In his notes, Mendeleev stated that he expected tellurium to have a lower atomic mass than iodine. However, all measurements continue to show that tellurium has a greater atomic mass than iodine even though tellurium acts like it has a lower atomic mass. What is the most likely reason that Mendeleev placed tellurium before iodine?
Mendeleev observed that tellurium has chemical properties like other elements in its group, and he did not know that neutrons cause the greater atomic mass.
Mrs. Rushing fills a balloon with hydrogen gas to demonstrate its ability to burn. Which combination could she use to produce the hydrogen she needs?
Mg and HCl
Calculate the momentum of a 12ookg car with a velocity of 25m/s. p = mv = 1200 X 25 = 30,000kg.m/s
Momentum (practice problem #1)
A school bus traveling at 40 km/hr. (11.1m/s) has a momentum of 152625 kg.m/s. What is the mass of the bus? M = p/v = 152625/11.1 = 13,750kg
Momentum (practice problem #3)
A boy threw a powerade up to his girlfriend who was leaning out of the second-floor window, 12 meters up. The powerade stopped rising after 1.3 seconds. Did he throw the powerade high enough for her to catch it?
No
Dillon is conducting a survey about whether or not people like a traffic law that is being passed.Can he publish his findings as a scientific study because he collected information?
No, because his information is subjective.
Jamie is not sure a new medication will work because it has not had a large test group. Is Jamie being creative?
No, he is being skeptical.
Consider the three equations below. mc017-1.jpg mc017-2.jpg mc017-3.jpg Which statement do these reactions best support?
Nuclear fusion plays an important role in making elements that are heavier than helium.
Luis and Aisha conducted an experiment. They exerted different forces on four objects. Their results are shown in the table. Based on the data, which object has the greatest acceleration?
Object 3
Luis and Aisha conducted an experiment. They exerted different forces on four objects. Their results are shown in the table. Based on the data, which object has the greatest acceleration?
Object 3
Inelastic collision
Objects stick together, they either distort or generate heat
Which sequence furthers scientific knowledge?
Observations generate a scientific question, leading to a hypothesis, which can be tested through an experiment.
Why can evaporation be used to separate a mixture? Check all that apply.
One or more components has a lower boiling point than the desired component. -The mixture is a solution that contains a substance that will crystallize out. -Heat causes some of the components to change into a gas.
In a science demonstration, a teacher mixed zinc (Zn) with hydrogen chloride (HCl) in a flask and quickly attached a balloon over the mouth of the flask. Bubbles formed in the solution and the balloon inflated
One or more new substances formed.
In a science demonstration, a teacher mixed zinc (Zn) with hydrogen chloride (HCl) in a flask and quickly attached a balloon over the mouth of the flask. Bubbles formed in the solution and the balloon inflated. What most likely occurred during this demonstration?
One or more new substances formed.
"Na2SO3" represents sodium sulfite. What does the 4 mean in the formula 4Na2SO3?
There are four molecules of sodium sulfite.
How do the nuclei of covalently bonded atoms help keep the bond together?
Positive particles in the nucleus are attracted to shared electrons, so the atoms stay close together.
Which description explains how inertia changes the effects of gravity on objects in the solar system?
Prevents planets from pulling into one another
The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance lose energy during a change of state. Before the change, the atoms are close together but are able to slide past one another. Which arrow represents the change of state described above?
Q
The part of the electromagnetic spectrum that has the longest wavelengths is _____.
RADIO WAVES
View the spinner. On which colors is it equally likely that the spinner will land?
Red and Blue
Explain the difference between repetition and replication.
Repetition refers to performing multiple trials throughout an experiment. Repetition reduces mistakes and increases one's confidence in the results. Replication refers to the ability of a process to be repeated by another individual. When a scientist replicates the experiment of another, the experiment should produce the same results.
You can use an arrow to represent the direction and strength of a force. The direction of the arrow represents the direction of the force. The length of the arrow represents the strength, or magnitude, of the force
Representing Force
Hallie takes notes in class as shown below. Developed through making observations About the natural world Observation → question → hypothesis → experiment Which would be the best title for her notes?
Scientific Knowledge
When people look through a telescope, air currents in the Earth's atmosphere can distort the images they see. In the 1950s, a scientist named H. W. Babcock thought of a way to reduce this distortion by using a special device within the telescope. However, this device was not used until the 1990s. Which best explains why Babcock's idea took many years to become a reality?
Scientific ideas often have to wait until advancements in technology make the ideas possible.
Elena makes the table below to determine the number of atoms of each element in the chemical formula 3(NH4)2SO4.
She should not have multiplied the sulfur atoms by the subscript 4.
Which scenarios are examples of physical changes? Check all that apply.
Silicon is cut into tiny pieces for computer chips. Lead is melted to form pellets. Liquid water freezes to form ice
Read the passage about the health risks of single-load liquid laundry packets. These packets are filled with concentrated, toxic chemicals. A 7-month-old in Florida died from swallowing the soap. Several soap and detergent companies are conducting studies to address these safety concerns; they want to reduce toxicity and to make the packets look less like candy. The U.S. Consumer Product Safety Commission (CPSC) is also performing studies to build more safety into these products. Why would the CPSC perform studies when other soap and detergent companies have already conducted research on the same products?
Studies performed by the CPSC give reliability to the results of improved safety obtained by each soap company.
Hector uses the apparatus below to separate a mixture. How do the substances compare?
Substance 1 has a higher boiling point than Substance 2.
Three treatments of different starting materials are listed. Which statement explains the treatments?
Substance 1 was activated by the heat and inactivated by ice, Substance 2 was activated by the change in concentration, and Substance 3 increased the surface area.
Almost all energy on Earth comes from the ____.
Sun
If there are 2 cars with the same mass but one has doubled the speed
That car will have double the momentum
Which best defines the relationship between speed and velocity?
Velocity is speed with displacement.
Shiloh wanted to observe the changes that occurred during an exothermic reaction. He monitored the changes and placed them in a chart. Which statement best describes his data?
The activation energy was reached was 10:45 a.m. The additional energy did not affect the reaction.
The equation below shows a general equation for a reaction, and the amounts of the substance are written underneath. AB + CD → AC + BD (15 g) (?) (?) (10 g) The total mass of the products is 50g. Which best completes the other two amounts?
The amount of CD is 35 g, and the amount of AC is 40 g.
Heartburn is a form of indigestion felt as a burning sensation in the chest when stomach acid comes back up into the esophagus. Some people take an antacid to relieve heartburn. Which best describes the antacid's effect?
The antacid is basic and will neutralize the acid entering the esophagus.
Three grams of the same substance in different phases are stored in three different containers. Each container is barely large enough to hold the substance. Which statement can be known about the behavior of the atoms in each container?
The atoms in the solid would be vibrating in position
A ball is thrown forward at 5 m/s. How would the path of the ball differ on Earth than on the moon?
The ball would curve down more sharply on Earth than on the moon.
Which property of physical changes explains why matter is conserved in a physical change?
The bonds between atoms do not break; it is only the arrangement that changes.
Ronald makes his own chicken broth. He uses the tool shown below to separate the broth from the fat. Why does this tool work to separate the mixture?
The broth has a higher density than the fat.
Which is a property of every heterogeneous mixture?
The characteristics of the mixture change within a sample.
Obi is trying to determine if a powdery, solid substance is an element or a compound. After recording some observations, he strongly heats a sample of the solid over a burner flame. After fifteen minutes, he turns off the flame and allows the sample to cool. He records his final observations in the data table.
The chemical reaction with acid changed, showing that the sample was broken down by heating. Therefore, the original substance is a compound.
Scientists have changed the model of the atom as they have gathered new evidence. One of the atomic models is shown below. What experimental evidence led scientists to change from the previous model to this one?
The colors of light emitted from heated atoms had very specific energies.
The results of a dart game were precise but not accurate. The accepted value of the game was the center of the dartboard. Which correctly describes the results?
The darts hit the same general area of the board.
What does it mean if data are reproducible but not accurate?
The data can be produced over and over but are not close to the accepted value.
An amount of nitrogen undergoes a physical change and increases its volume. What can be known about this physical change?
The density changed
When 2 objects recoil, the objects have
The exact same momentum as each other
Maggie is a member of her school's environmental club and is interested in recycling. She asks the question, "How does exposure to the environment affect recyclable plastics?"
The focus of the question is too broad, so it should be narrowed to a single environmental factor.
Density involves the amount of a material in a certain volume. When a material changes phases, it changes in density in a predictable way as the amount of material stays the same but the molecules get farther apart or closer together. Water has solid and liquid states that do not follow these predictions of density in the phases of matter. What does that mean about the densities of the phases of water?
The liquid state is more dense than the solid state.
Scientists launch a rocket, and they monitor its acceleration and the force exerted by its engines. As the rocket gets higher, the monitors show that the acceleration of the rocket is increasing but the force exerted stays the same. How do Newton's laws explain why the scientists could expect this to happen?
The mass of the rocket decreases as fuel is burned, so the acceleration increases
Scientists launch a rocket, and they monitor its acceleration and the force exerted by its engines. As the rocket gets higher, the monitors show that the acceleration of the rocket is increasing but the force exerted stays the same. How do Newton's laws explain why the scientists could expect this to happen?
The mass of the rocket decreases as fuel is burned, so the acceleration increases.
Separating by magnetism
The screening method can be very effective, but when it comes to separating certain elements, there can be an even more effective method. Suppose you accidentally knocked over a box of nails into some dirt. How would you get the nails out? Obviously, you could just pick them up (an application of separating a mixture on the basis of particle size, texture, and color) or use the screening technique, but the nails have another physical property that you could use to quickly remove them from the dirt—magnetism. Moving a magnet over the dirt would be an efficient way to gather the nails. Whenever a substance containing iron needs to be removed from a mixture, you should consider using a magnet.
Which is true about dissolving a polar substance in water?
The solute particles are carried into the solution.
The compound magnesium phosphate has the chemical formula Mg3(PO4)2. In this compound, phosphorous and oxygen act together as one charged particle, which is connected to magnesium, the other charged particle. What does the 2 mean in the formula 5Mg3(PO4)2?
There are two phosphate ions in a molecule of magnesium phosphate.
Levi and Clara are trying to move a very heavy box. Levi is pushing the box with a force of 30 N, and Clara is pulling the box with a force of 50 N. The box exerts a frictional force of 65 N. Which best explains the forces?
There is a net force of 15 N allowing Levi and Clara to move the box.
Levi and Clara are trying to move a very heavy box. Levi is pushing the box with a force of 30 N, and Clara is pulling the box with a force of 50 N. The box exerts a frictional force of 65 N.
There is a net force of 15 N in the direction of Clara.
The table shows results of an experiment that was replicated. Which best describes the data?
They are precise and reproducible.
Uranium is an element that is often used in nuclear power plants. Uranium atoms are very large, and the substance can be dangerous if it is not carefully contained. What is true about all uranium atoms?
They each have the same number of protons.
Which is the balanced equation for V2O5 + CaS → CaO + V2S5?
V2O5 + 5CaS → 5CaO + V2S5
A boy whose mass is 37 kg runs at 5 m/s and jumps onto a 15 kg sled sitting still. The boy slides on the sled at a speed of what? (Find V 3)
V3= 3.6 m/s
If you know the distance and the time, what formula would you use to calculate the velocity?
V= d/t
The diagram shows Ned's movement as he left his house and traveled to different places throughout the day. Which reference point should be used to find out how far Ned traveled when he went from the pet store to the swimming pool?
W
A body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing.
Weight
A measure of the force of gravity pulling down on your body; unit for measuring weight is the Newton.
Weight
lthough related to each other, mass and weight are not the same. An object's weight is the product of the object's mass and acceleration due to gravity acting on it. Weight Formula. Weight = Mass x Acceleration due to gravity. W= mg. The value for g is 9.8 m/s2. Mass and weight are proportional. Doubling the mass of an object also doubles the object's weight. Mass is a measure of the inertia of an object; weight is a measure of the force of gravity acting on an object
Weight and Mass
Magnesium
What element have 2ve and 3 shells?
The momentum of any object that is at rest is zero
When is momentum = Zero
Explosion
When one object becomes many moving objects
Candace is interested in learning more about colors. Which question about colors could be answered through scientific investigation?
Which color bends the most to make a rainbow?
Bena thinks that dissolving more salt in water causes the mixture's freezing temperature to change. Which is the best type of scientific investigation for Bena to use to study this?
an experimental investigation, because it allows for the control of variables
Nami conducts an investigation on plants. She places a grow light on a timer to give the plants different amounts of light to see if this would affect their growth. In this investigation, the amount of light is the________
independent variable
Justin is making a snack. He toasts a piece of bread and spreads peanut butter and jelly on it. Then he cuts an apple into several slices and adds these to his plate. Next, Justin mixes a scoop of lemonade powder into a glass of water, mixes it, and adds ice. How many chemical changes occurred in this scenario?
one
A solution was made by completely dissolving 1200 g of table salt into 3 L of hot water. Then, the water was left to cool to room temperature. If the solubility of the salt is 36 g/100 mL water, which term best describes this solution at room temperature?
super
Which method would increase the solubility of a gas
temp
A boat travels 4,000 meters in 20 minutes. What is the boat's average velocity?
v=200 meters/ min
What two parts does a measurement have?
value and unit
what two parts does a measurement have?
value and unit
Which ingredient is added to a marinade to tenderize meat?
vinegar
A bicycle has a momentum of 36 kg • m/s and a velocity of 4 m/s. What is the mass of the bicycle?
9 kg
Katie rolls a toy car off the end of a table. Which path will the car follow when it leaves the table?
C
Football helmets are made with padding that helps reduce head injuries when a player collides with an object. Which best explains how the padding reduces injuries?
It extends the time of the collision
In a car, how does an air bag minimize the force acting on a person during a collision?
It increases the time it takes for the person to stop.
Objects 1 and 2 collide and stick together. Which best describes the momentum of the resulting single object?
It is equal to the momentum of object 1 plus the momentum of object 2.
When the mass is greater (at the same speeds), the momentum is greater. An object with a very small mass that has a lot of momentum because it is moving very quickly. MOMENTUM INCREASES WHEN EITHER MASS OR VELOCITY INCREASES!!
Mass and velocity and how it affects an object's momentum.
A bowling ball of 35.2kg, generates 218 kg.m/s units of momentum. What is the velocity of the bowling ball? V = p/m = 218/35.2 = 6.2m/s
Momentum (practice problem #2)
Which piece of furniture will have the most inertia and give the furniture movers the most difficulty in moving?
a 75kg dining table
When someone throws a ball, the action force is the person pushing on the ball. What is the reaction force?
The ball pushing the person
The speed of the object and the direction of its motion.
Velocity
The chart shows masses and velocities of four objects. Which lists the objects in order, from least to greatest momentum?
Y, W, X, Z
The chart lists the masses and velocities of four objects. Which object requires the greatest change in momentum in order to stop its motion?
Z
An object's resistance to any change in its motion is the ______ of the object
inertia
A force is a vector that has both ____ and direction.
magnitude
What must be included when describing the displacement of an object?
measurement and direction
Denise is riding her bike and falls to the ground. During the collision, she hits both grass and cement.
The grass extends the time of the collision
Which statement should she place in the region marked X?
NOT C,D
Acceleration of an object MUST be caused by a force that is ___________ than zero.
not
Carla's car needs antifreeze. How is antifreeze classified?
not weak acid strong base?
Read the claim about caffeine. Caffeine improves mental alertness and motor coordination. A university research study was conducted to examine how caffeine affects fine motor skills. Ten teen girls, ages 14 to 18, were given 200 mg of caffeine per day for 30 days. Thirty minutes after taking the caffeine, each subject took a timed fine motor skills test in which they fitted 20 small beads onto pegs. The graph compares each subject's average results on the same test done 30 minutes before and after taking the caffeine. Which groups would most benefit from the claim? Check all that apply.
-people who sell coffee with caffeine -diners that serve coffee with caffeine -soda manufacturers that sell caffeinated drinks -manufacturers of caffeinated energy sports drinks
Filtration
-process of collecting solid particles of a suspension on a filter
a boat travels 6,000 m in 40 minutes. whats the boats average velocity
2.5 m/s
What is 18,000 expressed in scientific notation?
1.8 × 104
The surface areas of four solutes are 2 mm2, 6 mm2, 10 mm2, and 4 mm2. Which solute will dissolve the quickest?
10 mm2
A force of 5 N accelerates an object. The object's mass is 50 g. What is the acceleration of the object? (Formula: F=ma)
100 m/s2
A force of 5 N accelerates an object. The object's mass is 50 g. What is the acceleration of the object? (Formula: F=ma)
100m/s2
you push a box with a force of 30 N on a frictionless horizontal floor snd the box accelerates at 2.5 m/s^2. what is its mass
12 kg
Jamal was riding his bike home at a speed of 12 mph. On his trip out, he had traveled 8 miles away from his house. He has been traveling for a half hour at this speed. How far away from home is he?
2 miles
What else is produced during the replacement reaction of silver nitrate and potassium sulfate? 2AgNO3 + K2SO4 → Ag2SO4 +
2KNO3
What else is produced during the replacement reaction of silver nitrate and potassium sulfate? 2AgNO3 + K2SO4 → Ag2SO4 +
2KNO3
What else is produced during the replacement reaction of silver nitrate and potassium sulfate? 2AgNO3 + K2SO4 → Ag2SO4 + |___|
2KNO3
A person rides a bike with a constant velocity of 2.5 m/s. If his total displacement was 8 meters, for how long was he riding?
3.2 Minutes
A ball has a mass of 140 g. What is the force needed to accelerate the ball at 25 m/s2? (Formula: F=ma)
3.5 N
An atom of the element zinc has an atomic number of 30 and a mass number of 65. How many protons does an uncharged zinc atom have?
30
An object has a mass of 5 kg. What force is needed to accelerate it at 6 m/s2? (Formula: F=ma)
30 N
the statement 300 kg per cubic meter represents
300 kg for each cubic meter, 300 kg for every cubic meter, and 300 kg divided by one cubic meter
When 560,000 is written in scientific notation, the power of 10 is
5
This is how krypton appears in the periodic table. Rounded to the nearest whole number, how many protons are in an atom of krypton?
36
Two carts collide and bounce apart. Cart 1 had a momentum of -6 kg • m/s before the collision. Cart 2 had a momentum of 10 kg • m/s before the collision. What is the total momentum of the carts after the collision?
4 kg m/s
1A, 3B, and 7A are examples of group on the periodic table. - names This is how zirconium appears in the periodic table. Rounded to the nearest whole number, how many electrons are in an atom of zirconium?
40
This is how zirconium appears in the periodic table. Rounded to the nearest whole number, how many electrons are in an atom of zirconium?
40
A car has a momentum of 20,000 kg • m/s. What would the car's momentum be if its velocity doubles?
40,000 kg m/s
A car has a momentum of 20,000 kg • m/s. What would the car's momentum be if its velocity doubles?
40,000 kg • m/s
the momentum of a 2,000 kg car traveling at 20 m/s is
40,000 kg*m/s
The gravitational force between two objects is 100 N. If the mass of each object is doubled, what is the gravitational force between the objects at the same distance?
400 N
The numbers represent the change in energy for a chemical reaction. Which numbers would result from an endothermic reaction? Check all that apply.
456 800 1
Ariana is accelerating her car at 4.6 m/s2. It took her 10 seconds to reach this acceleration. Her starting velocity was 0 m/s. What was her final velocity?
46 m/s
The number of hydrogen ions would equal the number of hydroxide ions in a solution with a pH of _____
7
shawna, who weighs 54 kg, is rollerblading on a level surface. if she is rolling at 12 m/s, to what height would she roll up an incline before stopping
7.3 meters
There are ____ atoms of oxygen in the chemical formula 2Ca(ClO2)2.
8
There are atoms of oxygen in the chemical formula 2Ca(ClO2)2.
8
There are___atoms of oxygen in the chemical formula 2Ca(ClO2)2.
8
If there is 8 g of a substance before a physical change, how much will there be afterwards?
8 g
Shane rides a motorcycle at an average speed of 35 mph for 2.4 hours. What is the distance he travels
84 Miles
a skydiver reaches an instantaneous velocity of 88.2 meters per second before opening his parachute. How long was he in free fall?
9 seconds
a bungee jumper falls off a tower and travels 2 seconds before the bungee cord starts to slow her down. what was her average velocity in free fall?
9.8m/s
the acceleration due to gravity is
9.8m/s^2 on earth, signified by the letter g, and a downward acceleration
The ancient Greek Scientist and philosopher made many scientific discoveries through careful observation and logical reasoning. Aristotle incorrectly proposed that force is required to keep an object moving at constant speed. This error held back progress in the study of motion for almost 2 thousand years
Aristotle (384 BC - 322 BC)
Which statements belong to Dalton's atomic theory? Select all that apply.
Atoms cannot be created or destroyed. Atoms cannot be broken down into smaller pieces. All atoms of an element are identical. Chemical reactions cause atoms to be rearranged.
Dalton
Billiard Ball Model, atoms form a compound, each element was composed of the same kind of atom
Which change of state has the wrong energy change listed?
Deposition
To break a chemical bond, particles need to collide with a certain amount of ______.
ENERGY
The force that attracts a body toward the center of the earth, or toward any other physical body having mass. For most purposes Newton's laws of gravity apply, with minor modifications to take the general theory of relativity into account. It is an attractive force, that is, it pulls objects together. Earth's gravitational force exerts a force of attraction on every other object that is near Earth. Earth's gravity acts downward toward the center of the Earth
Gravity
Three students are mixing the same type of solute in 500 ml of water. Jessica is heating her solution, Larry left his on the counter at room temperature, and Hunter is heating his solution while stirring it. Which ranks who would fully dissolve the solute, from first to last?
Hunter → Jessica → Larry
Which acid and base would you combine to form the salt Na₂SO₄?
H₂SO₄ and NaOH
When water (H2O) freezes into ice, some of the properties have changed but the of the H2O is the same.
Identity
The eagle. Because it has greater mass
If an eagle and a bumblebee are traveling at 8 km/hr, which has more momentum? Explain
In order to increase the final momentum of a tennis ball, you need to
Increase the force acting upon it Follow through when hitting the ball Increase the time of contact
Analyze the graph. Which months had rainfall between 10 and 20 inches each?
June, July, and September
The salt potassium chloride, KCl, can be formed by a reaction between
KOH and HCl.
What best describes the states of nonmetals when they are at room temperature?
Most nonmetals are gaseous, but some are liquid or solid.
What is the function of an electromagnet in an electric doorbell?
NOT A, B
Which object is the light most likely striking?
NOT B,D
According to Newton's first law of motion, the state of motion of an object does not change as long as the net force acting on the object is zero. Thus, unless an unbalanced force acts, an object at rest remains at rest, and an object in motion remains in motion with the same speed and direction
Newton's First Law of Motion
The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance lose energy during a change of state. Before the change, the atoms are close together but are able to slide past one another. Which arrow represents the change of state described above?
Q
An object at rest stays at rest and an object in motion stays in motion with the same speed and in the same direction unless acted upon by an unbalanced force.
State Newton's first law of motion in your own words.
Which liquid is the most viscous?
Syrup
Plants use sunlight as energy to convert carbon dioxide and water into glucose and oxygen. Which best describes the reaction?
The law of conservation of mass indicates the same amount of carbon will be found in the reactants as in the products.
An object is moving across a surface, but it does not gain or lose speed. Which best describes the object's force?
The net force is zero.
The diagram shows an electron shell model of a sodium atom. How would the model change as the atom forms bonds?
The third shell would be empty so that the eight electrons in the second level would be outermost after the atom loses one electron.
Law of conservation of momentum
The total momentum remains constant, it can be transferred, not created nor destroyed Momentum is transferred when objects collide
What is most likely true of an atom with a mass of 15 amu?
The total number of protons and neutrons is 15.
Hydrochloric acid and sodium hydroxide can be combined in equal ratios to form sodium chloride and water. Which best explains the reaction?
The total volume produced by combining hydrochloric acid and sodium hydroxide will result in the same volume of sodium chloride and water.
Sheila conducts an investigation to see how the amount of salt dissolved in water affects the density of the water. Which statement best describes the correct plan for her procedure?
The type of salt and the amount of water are controls, and the amount of salt and the density are variables.
The part of the electromagnetic spectrum that is necessary for the sense of sight in humans is ___.
VISIBLE LIGHT
Group 18; Noble gases
Which group are said to be electrically stable?
Different periods in human history are named for the materials used to make tools. Dr. Franklin is searching through layers of soil, looking for tools made by humans. After screening the top layer of soil, he uses a magnet to help speed up the search. Which type of location is Dr. Franklin most likely searching?
an Iron Age farm
The plum pudding model of the atom states that
an atom is made up of electrons in a sea of positive charges.
The release of a gas from a chemical reaction is very quick. A scientist wants to measure what is released, but in small increments. What would allow the scientist to change the rate of the reaction so the results could be measured?
an inhibitor
Which actions represent endothermic reactions? Check all that apply.
an instant ice pack becoming cold water boiling and creating steam gold melting
What is a salt?
an ionic compound that does not contain oxide or hydroxide anions
a position vs time graph that is a straight line could represent
an object with a constant velocity
Which element's symbol could replace the question mark in the diagram?
arsenic (As)
Rhonda watched a video taken by a camera that was lifted into the upper atmosphere by a weather balloon. She saw the balloon pop when it reached a certain height. Afterward, Rhonda wondered what effect the air pressure at high altitudes has on the volume of gas in balloons. What scientific practice is Rhonda performing?
asking a question
In an element's square on the periodic table, the number with the greatest value represents the
atomic mass.
Lionel has a hot plate, a thermometer, a container of water, a spoon, and a small hammer. Using these tools, Lionel can test several properties of an ionic compound; however, he will be unable to test the compound's
atomic structure
Metal atoms tend to give away valence electrons when they bond with nonmetal atoms. What type of bond will form between the metal and nonmetal atoms and why does this bond form?
b. An ionic bond will form because electrons are transferred.
Kaylee wants to test her hypothesis that she performs better on tests after getting more sleep.In which way will she best be able to do this?
by analyzing her average test scores after nights with different amounts of sleep
Cookware companies have been using a chemical called C-8, which helps to create a nonstick coating to pans. However, the Environmental Protection Agency (EPA) recently claimed that the use of C-8 in the manufacturing of nonstick cookware should be discontinued because studies show it causes cancer. Who might benefit financially the most from the EPA's claim?
cookware manufacturers who make pans out of steel only
Kiley wants to balance the equation H2 + N2 → NH3. Which would be her first step in balancing an equation?
creating a chart that shows the number of atoms in the reactants and products
Ella makes this table to organize her notes on whether atoms gain or lose energy during the changes of state. Which changes of state should she place in the column titled "Lose Energy"?
freezing, deposition, and condensation
The ___ of a wave is the number of wavelengths that pass a fixed point in a second.
frequency
A machine can never be 100% efficient because some work is always lost due to ______.
friction
a 20-kilogram object falls 2.0 meters to the floor. at what point in its fall does the kinetic energy if a body equal its potential energy
halfway to the floor
The type of chemical bond that involves the transfer of electrons between atoms is a(n) ______
ionic
Different ______ of an element have different numbers of neutrons.
isotopes
work may be measured using units of
joules
In which phase(s) of matter are the atoms closely packed but still able to slide past each other?
liquid
A(n) _____ is produced around a wire when an electrical current is in the wire.
magnetic field
Which statement best defines the relationship between work and energy?
not d. Work can transfer energy between objects and cause a change in the amount of total energy.
Students are studying the changing concentration of carbon dioxide levels in different substances. They insert sensors into each substance and allow a device to graph the results. What are the students most likely using?
probeware
a 15 kg baseball is thrown at a speed of 50 meters per second and a 7.25 kg bowling ball rolling at 2 meters per second are both stopped in 0.2 seconds.
the baseball is stopped with less force because it had less momentum
What does the current model of the atom look like?
the current model of an atom has a nucleus in the center, and many electron clouds orbiting around it.
Veronica's velocity was measured as 4.3 m/s. She displaced 20 meters in 4.7 seconds. Which piece of information is missing for the correct calculation of velocity?
the direction
Kaitlin is pushing her little brother in a swing. If her little brother weighs 27 kg, how much higher does Kaitlin need to push him to increase his potential energy to 350 joules?
x= 1.32m