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Name ___________________________
Chapter 4
Class ___________________
Date _____________
Atomic Structure
Chapter Test A
Multiple Choice
Write the letter that best answers the question or completes the statement on
the line provided.
1. Democritus thought that matter was made of tiny particles
a. of earth, air, fire, and water.
b. that could not be divided.
c. that could be divided.
d. that were all round and smooth.
2. 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?
a. 6 grams
b. 12 grams
c. 18 grams
d. 24 grams
3. Which of the following most accurately represents John
Dalton’s model of the atom?
a. a tiny, solid sphere with an unpredictable mass for a
given element
b. a hollow sphere with a dense nucleus
c. a tiny, solid sphere with a predictable mass for a given
element
d. a sphere that is hollow throughout
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4. J.J. Thomson’s experiments provided evidence that an atom
a. is the smallest particle of matter.
b. contains negatively charged particles.
c. has a negative charge.
d. has a positive charge.
5. Rutherford’s gold foil experiment provided evidence for
which of the following statements?
a. Negative and positive charges are spread evenly
throughout an atom.
b. Alpha particles have a positive charge.
c. Gold is not as dense as previously thought.
d. There is a dense, positively charged mass in the center of
an atom.
6. Which statement best describes Rutherford’s model of the
atom?
a. It is like an avocado with the pit representing the nucleus.
b. It is like an aquarium with swimming fish representing
positive charges.
c. It is like a fried egg with the yolk representing the
nucleus.
d. It is like a huge stadium with a positively charged marble
at the center.
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Chapter 4 Test A
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Name ___________________________
Class ___________________
Date _____________
7. Which statement about subatomic particles is true?
a. Protons, neutrons, and electrons all have about the
same mass.
b. Unlike protons or neutrons, electrons have no mass.
c. Neutrons have no charge and no mass.
d. An electron has far less mass than either a proton or
neutron.
8. Which of the following is unique for any given element?
a. the number of neutrons
b. the charge on the electrons
c. the number of protons
d. the mass of a neutron
9. Suppose an atom has a mass number of 35. Which statement
is true beyond any doubt?
a. The atom has an odd number of neutrons.
b. The atomic number is less than 17.
c. The atom is not an isotope.
d. The number of protons in the nucleus does not equal the
number of neutrons.
10. Which statement is true about oxygen-17 and oxygen-18?
a. They do not have the same number of protons.
b. Their atoms have an identical mass.
c. They are isotopes of oxygen.
d. The have the same mass number.
12. Which statement accurately represents the arrangement of
electrons in Bohr’s atomic model?
a. Electrons vibrate in fixed locations around the nucleus.
b. Electrons travel around the nucleus in fixed energy levels
with energies that vary from level to level.
c. Electrons travel around the nucleus in fixed energy levels
with equal amounts of energy.
d. Electrons travel randomly in the relatively large space
outside the nucleus.
13. What do scientists use to predict the locations of electrons in
atoms?
a. probability
b. algebra
c. geometry
d. ratios and proportions
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Chapter 4 Test A
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11. How was Bohr’s atomic model similar to Rutherford’s
model?
a. It assigned energy levels to electrons.
b. It described electron position in terms of the electron
cloud model.
c. It described how electrons gain or lose energy.
d. It described a nucleus surrounded by a large volume
of space.
Name ___________________________
Class ___________________
Date _____________
14. Which statement about electrons and atomic orbitals
is NOT true?
a. An electron has the same amount of energy in all orbitals.
b. An orbital can contain a maximum of two electrons.
c. An electron cloud represents all the orbitals in an atom.
d. An atom’s lowest energy level has only one orbital.
15. The glowing of a neon light is caused by electrons emitting
energy as they
a. move from lower to higher energy levels.
b. collide with other electrons.
c. move from higher to lower energy levels.
d. collide with the nucleus.
Completion
Complete each statement on the line provided.
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1. Unlike Democritus, Aristotle did not believe that matter was
composed of tiny, indivisible
.
2. John Dalton observed that elements always combine in the same
ratio to form a particular
.
Figure 4-1
3. In Rutherford’s gold foil experiment, shown in Figure 4-1, alpha
particles that bounce straight back from the foil have struck
in the gold atoms.
4. The region in which an electron is most likely to be found is called
a(an)
.
5. An atom in which an electron has moved to a higher energy level
is in a(an)
state.
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Chapter 4 Test A
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Name ___________________________
Class ___________________
Date _____________
Short Answer
Use complete sentences to write the answers to the questions on
the lines provided.
1. What scientific word comes from a Greek word meaning “uncut”?
Which Greek philosopher first used the word to describe matter?
2. If an atom of an element has a mass number of 31 and 16 neutrons
in its nucleus, what is the atomic number of the element?
3. If an atom of germanium has a mass number of 70 and an atomic
number of 32, how many neutrons are in its nucleus?
4. What did Bohr’s model of the atom do that Rutherford’s model
did not?
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Chapter 4 Test A
© Pearson Education, Inc. All rights reserved.
5. How does the electron cloud model of the atom represent the
locations of electrons in atoms?
Name ___________________________
Class ___________________
Date _____________
Using Science Skills
Use the diagram to answer each question. Write the answers on a separate
sheet of paper.
Figure 4-2
1. Analyzing Data What subatomic particles are represented in
Figure 4-2? Assuming all the particles in the nucleus are visible,
what are the atomic and mass numbers of the atom shown?
2. Inferring Would Dalton have recognized the model of a nucleus
shown in Figure 4-2? Explain your answer.
3. Inferring Would Rutherford have recognized the model of a
nucleus in Figure 4-2? Explain your answer.
4. Inferring Why do you think the proton was discovered before the
neutron? (Hint: Consider the properties of protons and neutrons.)
5. Evaluating Is Figure 4-2 a useful model of an atom? Explain
your answer.
Essay
© Pearson Education, Inc. All rights reserved.
Write the answer to each question on a separate sheet of paper.
1. Why did Rutherford propose a new model of the atom after seeing
the results of the gold foil experiment?
2. A sample of calcium contains calcium-40, calcium-44, calcium-42,
calcium-48, calcium-43, and calcium-46 atoms. Explain why these
atoms can have different mass numbers, but they must have the
same atomic number.
3. Why is Bohr’s model of the atom often called the planetary
model?
4. What is the difference between an orbital and the electron cloud?
5. Explain what the colors in a fireworks display reveal about the
movement of electrons in atoms.
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Chapter 4 Test A
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