bill nye de science gi
which two elements have the same number of valence electrons?
Cl and F
which is the correctly balanced equation?
Cl2 Nal > 2NaCl2
which compound is most affected by a change in temperature from 30 -C to 50 -C
CsNO3
a scientist uses litmus paper to measure the pH of several different solutions. which solution turns the litmus paper red?
HCl
which is the chemical formula for magnesium hydroxine?
Mg(OH)2
a ball with a mass of 5 kg is dropped from a resting position 10 m above the ground. what is the potential energy of the ball just before it is dropped?
245 J
HgO > Hg + O2. which equation is the correctly balanced chemical equation for this reaction?
2HgO > 2Hg +O2
a flashlight bulb connected to a 6-V battery draws a 0.5-A current. what is the power used by the flashlight bulb?
3 W
which is a correctly balanced chemical equation?
3CuCl2 + 2Al > 2AlCl3 + 3Cu
which is a correctly balanced chemical equation?
3CuCl2 + 2Al > 2AlCl3 +3Cu
a 100-gram sample of radium-226 has a half life of 1,600 years. how long will it take before there are only 12.5 grams of the radioactive radium-226 remaining?
4,800 years
an object has a mass of 12.8 kg and a velocity of 8.4 m s. what is the kinetic energy of the object?
451.6 J
how many protons and neutrons does boron-11 have?
5 protons, 6 neutrons
this graph shows the motion of a car. what distance has the car traveled in 10s?
50 m
how much power is used to lift a box that weighs 50 newtons 10 meters in 10 seconds?
50 watts
this diagram shows an object being pushed along a frictionless surface. the object accelerates at 2 m/s/s. what force was applied to the object?
6 N
a total of 750 J of work was done when a force of 125 N was exerted on a box to ______. how far was the box moved?
6.00 m
an atom has 29 protons, 29 electrons, and 35 neutrons. what is the mass number of the atom?
64
a large rock has a mass of 750 kg. what is it's weight?
7,350 N
at which temperature does KCI have the same solubility as CuSO4?
73*C
if 15 N of force are applied to a cart to move it a distance of 5 m, how much work is done on the cart?
75 J
a cars velocity changes from 0 m/s to 40 m/s in 5 seconds. what is the average acceleration of the car?
8 m/s/s
which compound is most likely formed using covalent bonds?
SiO2
two boxes, X and Y, are on a shelf 10 meters above the floor. Box X has a mass of 4 kg. which statement best represents the relationship between boxes X and Y?
box X has less potential energy that Box Y
which element is represented?
bromine (Br)
which is an example of a mixture?
bronze pipe
if bulb 3 burns out in the circuit, what will most likely happen?
bulb 1 and bulb 2 will not glow
how could the strength of an electromagnet be increased ?
by increasing the number of coils in the wires of the electromagnet
how can two different nonmetals form a compound?
by sharing electrons
which action will have the least effect on the strength of an electromagnet?
changing the currents direction
a metal spoon is used to stir a pot of boiling water. the person holding the metal spoon feels the spoon get hot. which best describes the transfer of heat in the spoon?
conduction
which accounts for most of the mass of an atom?
neutrons and protons
which type of friction occurs when an eraser is rubbed across a sheet of paper?
sliding
which is the correct name for the compound NaNO3?
sodium nitrate
student X pushes a 10-N box with a force of 2 N. at the same time, student Y pushes the same box with a force of 6 N, but in the opposite direction. which will most likely occur?
the box will move towards student X
when the card is given a hard horizontal push to the right, what will happen?
the card will fall off the cup, but the quarter will fall directly into the cup
what would happen if the voltage were doubled?
the current would double
the board exerts an upward force of 50 N. which best explains this situation?
the cylinder has a weight of 50 N
two students pull on the opposite ends of a rope, but neither student is able to move the other. which statement bests explains why neither student is moved?
the each pull on the rope with the same amount of force, so the net force is zero
why does the weight of an object change with increasing elevation on Earth?
the force of gravity acting on the object decreases with higher elevation
why does a flat piece of notebook paper take longer to reach the ground than an identical piece of notebook paper crumpled up into a ball?
the frictional force of air has more effect on the falling flat piece of paper
what describes the kinetic energy of a ball in free fall?
the kinetic energy increases because the velocity increases
two magnets are stuck to end by a magnetic force. which statement best describes these magnets?
the north pole of one magnet is attracted to the south pole of the other magnet
how does the speed of the cart compare when t = 6s and t = 12s?
the speed of the cart is 0.5 m/s at 6s and 12s
a person places a metal spoon that is at room temperature into a bowl of hot soup. how will the thermal energies of the spoon and the soup be affected?
the spoon will increase in thermal energy, and the soup will decrease in thermal energy
if the north poles of two bar magnets are brought together, which is true?
the two north poles will repel each other
which best describes alpha particles
they are attracted to negative electric fields
which is true of infrared waves?
they have longer wavelengths than ultraviolet waves
what happens to the molecules in a pot of water as it is heated?
they move faster
which type of wave is represented?
transverse wave
which is the lowest point of a transverse wave?
trough
this diagram shows a marble with a mass of 3.8 g that was placed in 10 mL of water. What is the density of the marble?
1.27 g/cm63
when the equation is balanced, which coefficient should be placed before NaCl?
2
when the quation is balanced, which coefficient should be placed NaCl?
2
this diagram represents a closed circuit. how much current flows through this circuit?
2 A
which best describes the structure of fluorine-19
2 electrons in the first energy level; 7 electrons in the second energy level
this graph represents the velocity of an object over time. What is the average acceleration of the object during the first 4 seconds?
2 m/s/s
a student moves a box across the floor by exerting 23.3 N of force and doing 47.2 J of work on the box. how far does the student move the box?
2.03 m
what is the melting point of this substnace?
20 C
a car starts from rest and accelerates uniformly at 1.7 m/s/s. how long will it take the car to reach a speed of 34 m/s?
20 s
which compound results from covalent bonding?
C6H12O6
which element is an alkaline earth metal?
Ca
which compound will most likely be formed when lithium (Li) and nitrogen (N) are chemically combined?
Li3N
a solution of which compound has a pH greater than 7?
LiOH, because it's a base
atoms of which two elements will form an ionic bond?
Mg and Cl
some coins are alloys of zinc (Zn) and copper (Cu). which type of bond forms these coins?
metallic
which chemical equation represents a double replacement reachtion?
NaOH HCI > NaCl H2O
which element has the same number pf valence electrons as krypton?
Neon (Ne)
which type of chemical bond accounts for the high electrical conductivity in a bar of pure silver (Ag)?
metallic
if it took 5.38s to reach the final velocity, which train had the greatest acceleration?
W
a roller coaster car moves on a roller coaster track through positions W, X, Y, and Z. at what position will the roller coaster car most likely have the greatest kinetic energy?
X
object C and object Y are rubbed together . object X acquires a negative charge. what does object Y experience?
a loss of electrons
an element located at group 18 period 4 would be classified as which type of substance?
a nonmetal
based on the information, what best describes this solution?
acid
which is a true statement about a series circuit?
all the current flows through every part of the circuit
which group is in order of increasing ability to penetrate an object
alpha, beta, gamma
a gas has a volume of 4.52 L. if its mass is 8.05 g, what is the identity of the gas?
argon
why are beta particles able to penetrate objects better than alpha particles are?
because beta particles are smaller than alpha particles
why does temperature remain constant from when t = 2 min to when t = 5 min?
because heat energy is released from the substance as it changes from a liquid to a solid
which statement best explains why there could be a force of attraction between two electrically charged objects
because they have unlike charges
which substance is most basic?
bleach
which type of chemical reaction is represented
double replacement
which type of chemical reaction is represented?
double replacement
which statement best describes a bar magnet that has been broken into two pieces?
each piece has both a north and south pole
in cars with electric door locks, electromagnets allow the doors to be locked and unlocked at the push of a button. why is an electromagnet used for this kind of door lock?
electromagnets can easily be turned off
which substance is most likely classified as a colloid?
fog
a gemstone has a mass of 6.24 g and a volume of 1.98 cm63. What is the identity of the gemstone?
garnet
how does ice cool a warm drink?
heat flows from the drink to the ice
why does a student's hand feel cold when holding an ice cube?
heat flows from the hand to the ice cube
how does a step-down transformer alter the amount of voltage from a power line to a building?
it decreases output voltage by decreasing the number of turns in the secondary coil
how would decreasing the diameter of the wires in a circuit influence the resistance and flow of electrons in the circuit?
it would increase the resistance, causing fewer electrons to flow through the circuit
a ball at rest is dropped and hits the ground in 1.5 s with a final speed of 15 m/s. how would the acceleration and final speed of the ball be affected if it were dropped from a greater height on earth?
it's final speed would increase because it's rate of acceleration would remain the same
if light bulb 3 burns out in the circuit, what will happen to light bulb 1 and light bulb 2?
light bulb 1 and light bulb 2 will work
a teacher wants to demonstrate a chemical reaction to her students. which activity would best demonstrate a chemical reaction?
placing a metal in an acid to create a gas
which of the elements is the most chemically reactive?
potassium (K)
how do radio waves and visible light waves differ?
radio waves have a lower frequency than visible light waves
which of the following correctly shows the arrangement of the electromagnetic spectrum from longest wavelength to shortest wavelength?
radio waves, microwaves, infrared, visible, UV, x-rays, and gamma rays
a student wants to build a simple circuit. which material would be used to design a circuit with the least amount of resistance?
short wires with a large diameter
which elements are in the same period?
silver and tin
what type of chemical reaction is represented by this equation?
single replacement