1. When the Geiger Counter detector tube is moved three times closer to the
radioactive source, the counts per minute (cpm) should: A) triple B) decrease
3X C) increase 9X D) increase 27X
2. When Radium-226 transmutates into Radon-222, this is an example of: A)
alpha decay B) beta decay C) fission D) bombardment
3. Beta decay of Bismuth-214 results in formation of: A) Thallium-210 B)
Lead-214 C) Polonium-214 D) Polonium-210
4. For a radioactive sample to decay until only 6.25% of the original nuclei
were undecayed takes ___ half lives. A) 3 B) 4 C) 5 D) 6
5. When Al-27 is bombarded with an alpha particle, a single neutron is ejected
and the product is: A) P-31 B) Si-30 C) Si-29 D) P-30
6. When technetium-99m decays, its atomic number and mass number are unchanged.
This must be: A) alpha decay B) beta decay C) gamma decay D)
incorrect
7. A 400 microgram radioisotope sample with half life of 5 minutes decays
for 30 minutes; ____ then remains. A) 12.5 micrograms B) 6.25 micrograms
C) 3.125 X 10-6 grams D) 1.56 X 10-6g
8. Show the entire calculation of the average atomic mass of copper with
30.83% abundance Cu-65, mass = 64.93amu, and 69.17% abundance Cu-63, mass
= 62.94amu (atomic mass units)
9. Rutherford's Gold Foil Experiment found: A) existence of electrons B)
three kinds of radiation C) radioactivity D) none of these
10. Write the balanced nuclear equations for the alpha decay of U-238 and
the subsequent beta decay of Th-234.