Topic 3 Practice - The Atom
1. What is the number of electrons in an atom that has 3
protons and 4 neutrons?
A) 1
B) 7
C) 3
10. Experiments with gold foil indicated that atoms
D) 4
2. Which subatomic particles have a mass of approximately
1 atomic mass unit each?
A)
B)
C)
D)
proton and electron
proton and neutron
neutron and positron
electron and positron
11. Which equation represents natural transmutation?
A)
B)
C)
D)
3. What are the nucleons in an atom?
A)
B)
C)
D)
A) usually have a uniform distribution of positive
charges
B) usually have a uniform distribution of negative
charges
C) contain a positively charged, dense center
D) contain a negatively charged, dense center
protons and electrons
protons and neutrons
neutrons and electrons
neutrons and positrons
12. Given the nuclear reaction:
4. What is the total charge of the nucleus of a nitrogen
atom?
A) +5
B) +2
C) +7
What does X represent in this reaction?
D) +1
A)
5. Compared to an atom of phosphorus-31, an atom of
sulfur-32 contains
A) one less neutron
C) one more neutron
A) 7
B) 10
C) 3
C)
D)
13. The diagram below represents a nuclear reaction in
which a neutron bombards a heavy nucleus.
B) one less proton
D) one more proton
6. What is the total number of neutrons in an atom of
B)
?
D) 4
7. Chlorine-37 can be represented as
A)
1735Cl
B)
2037Cl
C)
3520Cl
D)
3717Cl
8. A sample of element X contains 90. percent 35X atoms,
8.0 percent 37X atoms, and 2.0 percent 38X atoms. The
average isotopic mass is closest to
A) 32
B) 35
C) 37
D) 38
9. Which fraction of an original 20.00-gram sample of
nitrogen-16 remains unchanged after 36.0 seconds?
A)
B)
C)
D)
Which type of reaction does the diagram illustrate?
A) fission
C) alpha decay
B) fusion
D) beta decay
14. Which particle can not be accelerated by the electric or
magnetic fields in a particle accelerator?
A) neutron
C) alpha particle
B) proton
D) beta particle
15. Which balanced equation represents a fusion reaction?
A)
B)
C)
D)
23592U
9336Kr + 14056Ba + 3 1 0 n
+ 10n
21H + 31H
4 2 He + 1 0 n
147 N + 4 2 He
178 O + 1 1 H
22688Ra
22286Rn + 4 2 He
Answer Key
Topic 3 - The Atom SHORT
1.
C
2.
B
3.
B
4.
C
5.
D
6.
D
7.
D
8.
B
9.
D
10.
C
11.
B
12.
B
13.
A
14.
A
15.
B