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1.  Answer Question 8 on the 1997 AP examination. (An example of an AP essay question.) 

2.  Answer Question 9 on the 1991 AP examination. (An example of an AP  essay question.) 

3.  What changes in a nuclide result from the loss of each of the following? 

1. An alpha particle.
2. A gamma ray.
3. An electron.
4. A positron.
5. A neutron.
6. A proton.

1. Bismuth-212 decays to polonium-212.
2. Uranium-230 undergoes alpha decay.
3. Beryllium-8 and a positron are produced by the decay of an unstable nucleus.
4. Fusion of a deuterium nucleus (²H) and a tritium nucleus (³H) giving a helium nucleus and a neutron.
5. A fission reaction producing Sb-133, Nb-99, and 4 neutrons following capture of a neutron by a U-235 nucleus.
6. The production of ¹⁴C from ¹⁴N by neutron bombardment.
7. The production of ²³⁹U from ²³⁸U by ²₁H bombardment.

6.  How does nuclear fission differ from nuclear fusion?  Why are both of these processes exothermic? 

7.  The iodine that enters the body is stored in the thyroid gland from which it is released to control growth and metabolism. The thyroid can be imaged if iodine-131 is injected into the body. In larger doses I-131 is also used as a means of treating cancer of the thyroid. I-131 has a half-life of 8.70 d and decays by e^- emission.  Emission of a gamma ray accompanies the beta decay. 

1. Write an equation for the decay.  (It is customary to omit gamma rays in nuclear equations that involve production of new nuclei or other particles.)
2. Is the beta particle or the gamma ray used in the imaging process?
3. How long will it take for 95.0% of a dose of  I-131 to decay. 

8.  Calculate the density of the ²⁴₁₂Mg nucleus in g cm^-3, assuming that it has the typical nuclear diameter of 1 x 10^-13 cm and is spherical in shape  (V = 4/3  r³

9.  What is the age of mummified primate skin that contains 8.25% of the original quantity of ¹⁴C?