1. AM 1 and AM 2 Review

2. 1. The three basic components of an atom are:
(a) protons, neutrons, and ions
(b) protons, neutrons, and electrons
(c) protons, neutrinos, and ions
(d) protium, deuterium, and tritium
Answer: b

3. 2. The identity of an element is determined by the number of:
(a) atoms
(b) electrons
(c) neutrons
(d) protons
Answer: d

4. 3. The nucleus of an atom consists of:

(a) electrons
(b) neutrons
(c) protons and neutrons
(d) protons, neutrons, and electrons
Answer: c

5. 4. A single proton has what electrical charge?
(a) no charge
(b) positive charge
(c) negative charge
(d) either a positive or negative charge
Answer: b

6. 5. Which particles have approximately the same size and mass as each other?
(a) neutrons and electrons
(b) electrons and protons
(c) protons and neutrons
(d) none - they are all very different in size and mass
Answer: c

7. 6. Which two particles would be attracted to each other?
(a) electrons and neutrons
(b) electrons and protons
(c) protons and neutrons
(d) all particles are attracted to each other
Answer: b

8. 7. The atomic number of an atom is:
(a) the number of electrons
(b) the number of neutrons
(c) the number of protons
(d) the number of protons plus the number of neutrons
Answer: c

9. 8. Changing the number of neutrons of an atom changes its:
(a) isotope
(b) element
(c) ion
(d) charge
Answer: a

10. 9. When you change the number of electrons on an atom, you produce a different:
(a) isotope
(b) ion
(c) element
(d) atomic mass
Answer: b

11. 10. According to atomic theory, electrons are usually found:
(a) in the atomic nucleus
(b) outside the nucleus, yet very near it because they are attracted to the protons
(c) outside the nucleus and often far from it - most of an atom's volume is its electron cloud
(d) either in the nucleus or around it - electrons are readily found anywhere in an atom
Answer: c

12. 11. The spontaneous disintegration of unstable nuclei by the emission of particles is called
a. radioactivity
b. spontaneous combustion
c. chemical decomposition
Answer: a

13. 12. An alpha particle has a. 2 protons and 1 neutron
b. 2 protons and 2 neutrons
c. 1 proton and 2 neutrons
Answer: b

14. 13. Fast moving electrons emitted by atomic nuclei are known as
a. alpha particles
b. beta particles
c. gamma rays
Answer: b

15. 14. When radioactive decay changes atoms of one chemical element into atoms of another element, the process is called
a. nuclear explosions
b. chemical decomposition
c. transmutation
Answer: c

16. 15. A thorium-232 atom undergoes alpha decay
15. A thorium-232 atom undergoes alpha decay. What element will be the product of this process?
a. radium
b. uranium
c. plutonium
Answer: a

17. 16. An atom of H-3 undergoes beta decay
16. An atom of H-3 undergoes beta decay. The element that will be produced is
a. hydrogen
b. helium
c. lithium
Answer: b

18. 17. The mass and charge of a gamma ray are
a. mass = 1 and charge = 0
b. mass = 0 and charge = 1
c. mass = 0 and charge = 0
Answer: c

19. 18. An isotope having a half-life of 5 years currently has an average activity of 600 counts /min. What was the approximate activity of this sample 15 years ago?
Answer: counts/min.

20. 19. The half-life of a radioactive isotope is 2. 0 hours
19. The half-life of a radioactive isotope is 2.0 hours. If you start with an 80 gram sample, how much of the original isotope will remain after 10 hours?
Answer: 2.5 grams

21. 20. Balance the following
______ + 10n → 14256Ba +9136Kr + 310n
23592U

22. 21. Determine the number of protons and electrons in the following ions
Ca +2
20 protons
18 electrons
N -3
7 protons
10 electrons