Chemistry Semester 1 Final
There are 1,343 megawatts of wind-generated electricity produced in Indiana every year. (Remember mega is 3 steps above kilo.) So... 1,343 megawatts is equivalent to
1,343,000,000 watts
How many electrons does Neon (Ne) have?
10
What is 1 centimeter equal to?
10 millimeters
Which of the following conversion factors would you use to change 18 kilometers to meters?
1000 m = 1 km
On the Celsius scale, at what temperature does water boil?
100°
How many neutrons does Helium (He) have?
2
How is 0.00025 written in scientific notation?
2.5 x 10⁻⁴
How many significant figures in 21.000? Remember during notes this was the example where it's your birthday.
5
Match the state of matter with the speed of the atoms (5 is the fastest to 1 the slowest)
5 Gas 4 Solid 2 Liquid 3 Bose-Einstein Condensate 1
Timers at a swim meet used four different clocks to time an event. Which recorded time is the most precise?
55.254 s
Dalton said compounds always exist in the same proportions. Example: 2 grams of element X combine with 4 grams of element Y to form compound XY.How many grams of X would combine with 12 grams of Y to form the same compound? 2X ?X ------ = ------ 4Y 12Y
6 grams
If 2 grams of element X combine with 4 grams of element Y to form compound XY, how many grams of element Y would combine with 12 grams of X to form the same compound?
6 grams
Oxygen (O) has an atomic number of
8
Which of the following provides the BEST analogy for an electron in an atomic orbital?
A bee buzzing inside a jar
Which of the following is part of John Dalton's atomic theory?
A compound contains atoms of more than one element. All elements are composed of atoms. All the above
How are science and technology related?
Advances in one may lead to advances in the other because they are interdependent.
What is the symbol for aluminum?
Al
What is the most important safety rule?
Always follow your teacher's instructions and textbook directions exactly.
Which statement about subatomic particles is true?
An electron has far less mass than either a proton or neutron.
The symbol for gold is
Au
Which of the following Group 1A elements is the most reactive?
Cs (cesium)
Who provided evidence for the existence of a nucleus in an atom? (The answer may be found in other questions on this test.)
Earnest Rutherford
How does Earth science overlap with life science?
Earth science involves the study of systems that may include living organisms
Which statement accurately represents the arrangement of electrons in Bohr's atomic model?
Electrons travel around the nucleus in fixed energy levels with energies that vary from level to level.
Which of the following has the highest viscosity?
Honey
How was Bohr's atomic model similar to Rutherford's model?
It described a nucleus surrounded by a large volume of space.
Which of the following is a heterogeneous mixture?
Jar of mixed nuts
Which of the following is NOT one of the main ideas of physical science?
One of the main branches of natural science is biology.
Which statement about subatomic particles is NOT true?
Protrons and neutrons have the same charge
Which of the following statements is true about SCIENTIFIC LAWS?
Scientific laws summarize patterns found in nature.
Why are peer reviews important?
Scientists receive questions and criticism from their peers, and Data are checked for accuracy. all of the above
Which statement is true about the metalloid silicon?
Silicon is a better conductor of an electric current than sulfur is.
What is the difference between an atom in the ground state and an atom in an excited state?
The atom in an excited state has more energy but is less stable than the atom in the ground state.
What can you assume has happened if an electron moves to a higher energy level?
The electron has gained energy
What happens when the data in an investigation do not support the original hypothesis?
The hypothesis will be revised.
Rutherford's gold foil experiment provided evidence for which of the following statements?
There is a dense, positively charged mass in the center of an atom.
How do scientists who speak different languages make their data understandable to one another?
They all use SI (metric system).
Which statement is NOT true about the elements fluorine, chlorine, and iodine?
They have similar noble gases
Why are scientific models important?
They help visualize things that are very complex, very large, or very small.
Which of the following clocks offers the most precision?
a clock with a hand to measure the hour, a hand to measure the minutes, and a hand to measure the seconds
If an unknown substance CANNOT be broken down into simpler substances, it is
a compound and a element
A material that is malleable and conducts electricity is most likely
a metal
What is a physical or mental representation of an object or an event?
a model
What is a peer review?
a process in which scientists examine other scientists' work
Forces of attraction limit the motion of particles most in
a solid
Which substance has particles moving the slowest?
a solid
Which of the following most accurately represents John Dalton's model of the atom?
a tiny, solid sphere with predictable mass for a given element
Zero degrees K is
absolute zero
On the periodic table, elements ___________ have similar properties
all the above, they are in the same family, in the same column, and containing same number of valence electrons.
To keep them from reacting, some highly reactive elements are stored in
argon
The Greek philosopher Democritus began to use this word to describe a tiny piece of matter that cannot be divided?
atom
The Greek philosopher Democritus used what word for any tiny piece of matter that cannot be divided?
atom
One-twelfth the mass of a carbon-12 atom is used to define a(an)
atomic mass unit (amu).
Moving from left to right across a row of the periodic table, which of the following values increases by exactly one from element to element?
atomic number
What are the building blocks of all matter?
atoms
How do scientists communicate the results of investigations?
by publishing articles in scientific journals, and by giving talks at scientific conferences all of the above
Water is a compound because it
can be broken down into simpler substances. always has two hydrogen atoms for each oxygen atom. both are true
The standard on which the atomic mass unit is based is the mass of a
carbon-12 atom.
The type of graph used to show how a part of something relates to the whole is a
circle graph
What type of mixture has intermediat sized particles and scatters light?
collid
When a physical change in a sample occurs, which of the following does NOT change?
composition
If a material contains three elements joined in a fixed proportion, it is a(an
compound
Which of the following are pure substances?
compounds
In the current atomic model, positive charge is
concentrated in the center of an atom.
J.J. Thomson's experiments provided evidence that an atom
contains negatively charged particles.
The phase change in which a substance changes from a gas directly to a solid is
deposition
Which of the following phase changes is an exothermic change?
deposition
What is the relationship in which the ratio of the manipulated (x) variable and the responding (y) variable is constant? (X/Y=constant) When x goes up, y goes up.
direct proportion
What method can be used to separate parts of a liquid mixture when the entire mixture can pass through a filter?
distillation
What physical properties of nylon and leather make them good materials to use for shoelaces?
durability and flexibility
A substance that has high reactivity
easily combines chemically with other substances
Which part of the atom has ALMOST NO mass?
electron
Which part of the atom is negative?
electron
Which subatomic particle has a negative charge?
electron
A substance that is made up of only one kind of atom is a(an
element
Early scientists created the first thermometer when they discovered that if substances get warmer they also
expand
If you move a substance from one container to another and its volume changes, the substance is a
gas
At room temperature, none of the metals are
gases
Which of the following is malleable at room temperature?
gold
Which of the following is a characteristic of a mixture?
has varying properties
Which of the following gases emit colors when an electric current is applied?
helium and neon
A mixture that appears to contain only one substance is a(an)
homogeneous mixture.
As you move from left to right across a period, the number of valence electrons
increases
In Niels Bohr's model of the atom, electrons move
like planets that can change orbit
If the relationship between the manipulated variable and the responding variable is a direct proportion, then what will a line graph of this relationship look like?
line going up, to the right (/)
Figure 1-1 What type of graph is represented by Figure 1-1?
line graph
Matter that has a definite volume but no definite shape is a
liquid
In which step of the scientific method is information obtained through the senses?
making observations
Mendeleev arranged the known chemical elements in a table according to increasing
mass
The heat of fusion for water is the amount of energy needed for water to
melt
The phase change in which a substance changes from a solid to a liquid is
melting
Which of the following is NOT a pure substance?
milk
Compared with Group 1A elements, Group 7A elements have
more valence electrons.
The column on the far left of the periodic table contains the
most reactive metals
The glowing of a neon light is caused by electrons emitting energy as they
move from higher to lower energy levels.
A gas has
no definite shape or definite volume
Flammability is a material's ability to burn in the presence of
oxygen
Ninety-nine percent of all the matter that can be observed in the universe exists as
plasmas
Which part of the atom is positive?
protron
Which of the following is a mixture?
sand
Which of the following is a physical change?
sawing a piece of wood in half
What is a system of knowledge and the methods used to find that knowledge?
science
What is a well-tested explanation of a pattern, observation or experimental results?
scientific theory
A mixture can be classified as a solution, suspension, or colloid based on the
size of its largest particles.
Which of the following is NOT a branch of natural science?
social science
Which element is found in nature only in compounds?
sodium
Which list of elements contains only metals?
sodium, chromium, copper
This diagram shows the results of Rutherford's gold foil experiment. What caused some of the alpha particles to bounce straight back from the gold foil?
solid nuclei in the gold atoms
During the process of freezing matter
stays the same temperature.
The phase change in which a substance changes from a solid to a gas without changing to a liquid first is
sublimation
How is the atomic mass of an element determined?
take a weighted average of the masses of the isotopes present in nature
The usefulness of Mendeleev's periodic table was confirmed by
the discovery of elements with the properties that Mendelev said they would have.
What does the electron cloud model describe?
the most likely locations of electrons in atoms
The tendency of an element to react chemically is closely related to
the number of valence electrons in atoms of the element.
According to John Dalton's observations, when elements combine in a compound,
the ratio of their masses is always the same.
Filtration can be used to separate mixtures based on
the size of their particles
The atomic mass of an element is
the weighted average of the masses of an element's isotopes
An alkali metal has one valence electron, while an alkaline earth metal has
two
Which of the following is an example of a safe laboratory procedure?
tying back long hair and loose clothing
The phase change that is the reverse of condensation is
vaporization
Which of the following phase changes is an endothermic change?
vaporization
A substance has a melting point of 0ºC and a boiling point of 100ºC. The substance is most likely
water
Which of the following materials is useful for making molds because it has a low melting point?
wax