Chemistry CA 1 Practice
Some questions (c) 2015 by Region 10 Educational Service Center.
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1 What information needs to be included to make
4
A chemical is labeled as corrosive.
a testable hypothesis?
A
just a guess of what will happen
B
a prediction of the results that will be
observed and an explanation of why it will
occur
C
the definition of some of the terms in the
experiment and how the results will be
determined
Which of the following first aid measures would
D
a summary of the research done and the
be needed to prevent the danger from
impact the information will have on the
occurring?
experiment
A
Covering exposed skin with aprons and
gloves
2
Mendeleev's contribution to modern
chemistry was the discovery of the —
3
A
electron
B
noble gases
C
periodic table
D
atomic nucleus
B
Wearing flip flops or sandals in lab
C
Running water over the skin for 15 minutes
D
Spreading sand on the lab tables and the
floor
5
Students conduct a lab in which they
neutralize an acid. Which of the following is the
last thing students should do before leaving
the lab area?
A
disassemble the equipment
B
wash their hands
C
record their observations
Which of the following is the best estimate of
D
clean the lab tables
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the volume poured from the graduated
cylinder?
A
3.00 mL
B
3.60 mL
C
4.40 mL
D
4.60 mL
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6
Why is it important to make and test hypotheses?
A
It is a traditional step in the scientific method developed by the Greeks that is set as protocol.
B
It informs the researcher if they are right or wrong in their thinking about the experiment before it
began.
C
It provides testable statements that can be supported or not supported by observational evidence.
Hypotheses which have been tested and supported over a wide variety of conditions are
incorporated into theories.
D
It is additional information that can be used by other researchers in the same or different fields for
many different purposes.
7
When plotting experimental data on a graph,
which of the following is plotted on the x-axis
10
A team of students collects a sample of
rainwater in a graduated cylinder.
in most cases?
8
A
the independent variable
B
the dependent variable
C
time, in seconds
D
distance, in meters
Which of the following methods should be used
to determine whether a substance is a mixture
or a compound?
9
Which is the best estimate of the volume of
A
titration
the sample?
B
combustion
A
36.0
C
physical separation
B
37.0
D
chemical decomposition
C
43.0
D
44.0
An electric current is passed through a sample
of water, causing the sample to break down
into oxygen and hydrogen. Given this
information, which is the correct classification
for water?
A
atom
B
compound
C
element
D
mixture
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11
What is the definition of a scientific theory?
A
It is an explanation based on observation, experimentation, and reasoning that has been tested and
confirmed as a general principle helping to explain and predict natural phenomena.
B
It is a statement of fact meant to describe, in concise terms, an action or set of actions. It is generally
accepted to be true and universal, and can sometimes be expressed in terms of a single mathematical
equation.
C
It is a trial solution to a problem, often called an "educated guess”, because it provides a suggested
solution based on the evidence.
D
It is principles and procedures for the systematic pursuit of knowledge involving the recognition and
formulation of a problem, the collection of data through observation and experiment, and the
formulation and testing of hypotheses.
12 Which question would be best answered by a
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scientific investigation?
testing by various scientists and is generally
A
How much does 100 g of NaCl cost?
accepted as being an accurate explanation of
B
Why is Fe the chemical symbol for iron?
C
What are the three elements that make up
an observation?
H2 SO4 ?
D
Does adding MgCl2 lower the melting
point of water?
13
Which of the following undergoes extensive
A mixture of iron and sulfur can be separated
16
A
hypothesis
B
scientific law
C
scientific method
D
scientific theory
A student uses a centimeter ruler to measure
by attracting the iron particles with a magnet.
the length of the strip of litmus paper shown
If the iron and sulfur mixture is heated
below.
strongly, iron (II) sulfide forms, which is no
longer magnetic and cannot be separated by
physical methods. What is iron (II) sulfide?
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A
element
B
compound
C
homogenous mixture
Which measurement is closet to the actual
D
heterogeneous mixture
length of the litmus paper?
A
3.5 cm
Which of the following is a physical property?
B
3.75 cm
A
being black in color
C
4.0 cm
B
neutralizing acids
D
4.25 cm
C
burning with oxygen
D
releasing SO2 gas
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17
A student mixes 36.0 grams of silver nitrate
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Which statement is correct about a sample of
solution with 30.0 grams of sodium chromate
liquid water?
solution. The mass of the products, which
A
includes the resulting solution and
precipitate, is equal to 66.0 grams. Which of
the following best explains these results?
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A
law of conservation of mass
B
law of definite proportions
C
law of multiple proportions
D
law of conservation of energy
It has a definite volume and a definite
shape.
B
It has definite volume but no definite
shape.
C
It has no definite volume and no definite
shape.
D
It has no definite volume but has a
definite shape.
Which of the following is an example of an
extensive property?
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A
volume
B
malleable
C
luster
D
density
Students carefully pour three liquids into a
graduated cylinder.
The experiment is repeated, but liquid
glycerin, which is less dense than corn
syrup and more dense than water, is also
used. Which of the following best predicts the
position of the glycerin layer?
A
above the alcohol layer
B
above the corn syrup layer and below the
water layer
C
below the corn syrup layer
D
above the water layer and below the
alcohol layer
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21
Which order of the following steps shows the progression of how a scientific theory is developed?
1. A theory is created to give highly reliable explanations.
2. The hypothesis is tested and refined by several scientists over time.
3. A hypothesis is created to explain the natural or physical phenomena.
4. A theory can be changed as new discoveries and technology are developed.
5. Observations and measurements are made over natural and physical phenomena.
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23
A
1 2 3 4 5
B
5 4 3 2 1
C
5 3 2 1 4
D
3 5 2 1 4
Which of the following is a chemical property
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10.0 grams of water in the form of a solid has
of sodium?
a temperature of 0.0 °C. The cube of ice is
A
silver-white color
placed in a room with a temperature of 25.0
B
density of 0.968 g/cm³
C
soft at room temperature
The initial 10.0 grams of water is what kind of
D
tarnishes when exposed to air
property?
°C. The ice starts melting to form a puddle of
water.
A
personal
Which of the following is an example of a
B
chemical
scientific theory?
C
intensive
A
D
extensive
Matter is composed of discrete units
called atoms, as opposed to the idea that
matter could be divided into smaller
pieces indefinitely.
B
The nucleus is composed of protrons and
neutrons while electrons are located
outside of the nucleus.
C
D
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Students are given a solid sample and asked
to determine whether the sample is an
element, compound, or mixture. One student
observes that the sample is made up of
particles of different colors, sizes, and
If the atomic number is subtracted from
shapes. When the students break off a piece of
the number of protrons then the number
the sample, they notice that some particles
left over is the number of neutrons.
are softer than others and some shine while
Matter cannot be created nor destroyed.
others appear dull. What can the students
conclude about their sample?
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A
It is an element.
B
It is a compound.
C
It is a homogeneous mixture.
D
It is a heterogeneous mixture.
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26
Cu + 2 AgNO3 --> Cu(NO3 )2 + 2 Ag
30
Which is one way a chemical property can be
The two sides of the above equation appear
witnessed?
different. These differences are evidence of a
A
heating a substance to its boiling point
B
examining a substance under a
—
A
mass change
B
physical change
C
chemical change
D
temperature change
microscope
C
passing an electrical current through a
substance
D
observing how one substance interacts
with another
27
What is an intensive property?
A
a property that depends on the amount of
matter present
B
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Which property listed below is listed in the
wrong category?
intensive property
a property that does not depend on the
property
amount of matter present
C
a property that can be observed or
measured without changing the
composition of matter, such as mass or
volume
D
a property that changes the composition
of matter
28
Which of the following describes a chemical
extensive
conductivity
mass
boiling point
color
reactivity
volume
ductile
length
A
color
B
conductivity
C
boiling point
D
length
property of oxygen?
A
Oxygen liquefies under pressure.
B
An oxygen molecule may consist of two
or three atoms.
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C
The density of oxygen is 0.00133 g/cm3.
D
Oxygen reacts with iron to form rust.
During recycling, ground glass is melted
under light heat and poured into molds.
Which type of change occurs as the glass
melts?
A
change in state
B
change in mass
C
change in reactivity
D
change in composition
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32
How are hypotheses different from theories?
A
Hypotheses are predictions to experiments, while theories are explanations of how natural
phenomena work.
B
Hypotheses are just guesses, while theories are just guesses on how the world works.
C
Hypotheses are educated guesses, while theories are explanations for common everyday
experiments.
D
Hypotheses and theories can both be changed, but theories are always correct and hypotheses can
be right or wrong.
33
Around the turn of the twentieth century, English physicist J. J. Thomson discovered that cathode rays
are streams of negatively charged particles. Because he was able to produce cathode rays using various
kinds of metals, Thomson concluded that all atoms must contain these negatively charged particles.
From this discovery, to what ultimate conclusion regarding the structure of the atom did Thomson then
come?
A
The negatively charged particles found in cathode rays normally orbit the nucleus of the atom.
B
The number and arrangement of negatively charged particles in an atom are what give it its
chemical properties.
C
The mass of a negatively charged particle is so small that the atom must also consist of protons and
neutrons.
D
The atom must contain some positive charge as well as negatively charged particles, because an
atom is electrically neutral.
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35
Which of these elements is the most
36
Ernest Rutherford bombarded a piece of gold
electronegative?
foil with alpha particles. He found that most
A
argon
particles passed through the foil. However, a
B
chlorine
C
phosphorus
the following best describes Rutherford's
D
sulfur
discovery?
very small percentage of the particles were
deflected back toward their source. Which of
A
Gold atoms repel alpha particles.
Which of the following is a physical change?
B
A gold atom is mostly empty space.
A
iron rusting under water
C
Gold atoms emit alpha particles.
B
copper turning green in the air
D
Gold atoms are spherical in shape.
C
solid iodine subliming into a gas
D
hydrogen and oxygen producing water
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37
Which statement describes one of the main differences between a physical and a chemical change?
A
A chemical change involves reactants and products, whereas a physical change involves only
reactants.
B
A physical change is a change of state, whereas in a chemical change the substance keeps the same
form.
C
A physical change brings about a different form of the same substance, whereas a chemical change
forms a different substance.
D
A chemical change caused by adding or removing heat energy can usually be reversed, whereas a
physical change can generally not be reversed.
38
Which of these elements is the most reactive?
A
potassium
B
calcium
C
scandium
D
titanium
41
What is the trend of ionic radius?
A
Ionic radius increases from period 1 to
period 7. B
Ionic radius decreases from period 1 to
period 7.
C
Ionic radius increases in cations and
decreases in anions.
39
Which of the following is most likely a
D
characteristic of sulfur?
40
Ionic radius decreases from group 1
to group 18.
A
solid at room temperature
B
inert
C
good conductor of heat
losing two electrons?
D
metallic
A
beryllium
B
helium
C
lithium
D
oxygen
42
The atomic radius of magnesium is 150 pm. The atomic radius of strontium is 200 pm. Which element is most likely to ionize by
What is the atomic radius of calcium?
A
smaller than 150 pm
B
greater than 200 pm
C
between 150 and 200 pm
D
not enough information
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43
Mendeleev organized his periodic table in
order of increasing atomic —
A
mass
B
number
C
radius
D
stability
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44
The energy of violet light is approximately twice that of red light. How do the wavelengths of violet and
red light compare?
45
A
The wavelength of violet light is sometimes greater than and sometimes less than that of red light.
B
The wavelength of violet light is the same as that of red light.
C
The wavelength of violet light is approximately twice that of red light.
D
The wavelength of violet light is approximately half that of red light.
Which two factors of the electromagnetic
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radiation have an inverse relationship?
46
A
amplitude and nodes
B
energy and frequency
C
frequency and wavelength
D
wavelength and energy
Magnesium is an alkaline earth metal. With
which group of elements is magnesium most
atom of 3 01 4Si?
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48
nonmetals
B
noble gases
C
alkali metals
D
transition metals
Which part of an atom has the least mass?
A
electron
B
neutron
C
nucleus
D
proton
A
14 protons and 14 neutrons
B
14 protons and 16 neutrons
C
16 protons and 14 neutrons
D
16 protons and 16 neutrons
The energy level of an electron is most
closely related to its —
reactive?
A
How many protons and neutrons are in one
51
A
charge
B
mass
C
position
D
size
What is the ground state electron
configuration for arsenic?
A
1 s2 2s2 2 p6 3s2 3 p6 3 d1 04s2 4p 3
B
1 s2 2s2 2 p6 3s2 3 p6 4s2 4p3 4d1 0
C
1 s2 2s2 2 p6 3s2 3 p6 3 d1 04s2 4p 6
D
1 s2 2s2 2 p6 3s2 3 p6 4s2 4p 3
Which particles are represented by the dots
in Lewis dot diagram?
52
Any atom that is electrically neutral must
A
core electrons
contain —
B
valence electrons
A
more protons than electrons
C
protons
B
equal numbers of electrons and protons
D
all electrons
C
fewer neutrons than nucleons
D
equal numbers of nucleons and neutrons
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53
What is the electromagnetic spectrum?
A
B
57
Boron has the average atomic mass of 10.81
It is the range of wavelengths and
and has two naturally occurring isotopes.
frequencies that can be detected by the
Which isotope of boron is more abundant?
human eye.
A
Boron-10 is more abundant.
It is a measure of the absorption of
B
Boron-11 is more abundant.
radiation as a function of frequency or
C
Boron-10 and boron-11 have the same
wavelength.
C
abundance.
It is a range containing all of the possible
D
frequencies and wavelengths of
There is not enough information to make
that determination.
electromagnetic radiation.
D
It is a spectrum of frequencies of
electromagnetic radiation emitted by the
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lowest energy?
element's atoms when they are returned
A
to a lower energy state.
54
Which of the following waves would have the
Which element has the ground state
electronic configuration,
B
1 s2 2s2 2 p6 3s2 3 p6 4s1 ?
A
calcium
B
potassium
C
phosphorus
D
bromine
C
D
55
All three waves have the same energy.
If the wavelength in wave A is doubled, how
would its frequency change?
A
Wave A's frequency would be doubled.
B
Wave A's frequency would be cut in half.
C
Wave A's frequency would be multiplied
by a factor of four.
D
59
Which of the following is the correct Lewis
dot diagram?
A
B
Wave A's frequency would be cut by a
fourth.
C
56
Neon is a noble gas. Which of the following
describes neon?
A
Neon has a very low chemical reactivity.
B
Neon is highly electronegative.
C
Neon is a solid at room temperature.
D
Neon is a good conductor of heat.
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D
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