Nuclear Chemistry Test

1. Which group is in order of increasing ability to penetrate an object?

• alpha, gamma, beta

• alpha, beta, gamma

• beta, gamma, alpha

• gamma, beta, alpha

2. A 100-gram sample of radium-226 has a half-life of 1,600 years. How long will it take before there are only 12.5 grams of the radioactive radium-226 remaining?

• 1,600 years

• 3,200 years

• 4,800 years

• 6,400 years

3. Why are beta particles able to penetrate objects better than alpha particles?

• Because beta particles are larger than alpha particles.

• Because beta particles are smaller than alpha particles.

• Because beta particles are negatively charged, while alpha particles are neutral

• Because beta particles travel in a straight line, while alpha particles travel in waves

4. How do the nuclear reactions that power the Sun compare to the nuclear reactions that occur in a reactor at a nuclear power facility?

• The Sun is powered via nuclear fusion while a nuclear power facility harnesses energy from nuclear fission.

• The Sun is powered via nuclear fission while a nuclear power facility harnesses energy from nuclear fusion.

• Both the Sun and a nuclear power facility are powered by nuclear fusion reactions.

• Both the Sun and a nuclear power facility are powered by nuclear fission reactions.

5. What type of naturally occurring radioactivity results in an increase in atomic number of an atom?

• fusion

• alpha decay

• beta decay

• gamma rays

6. When two nuclei are combined into one nucleus, there is a slight change in mass and the release of a large amount of energy. What is this process called?

• conversion

• reaction

• fission

• fusion

7. What particles are the products of the natural radioactive decay of an atom of Uranium-238?

• thorium-234 and an alpha particle

• radium-226 and an alpha particle

• uranium-234 and a beta particle

• polonium-218 and a beta particle

8. A radioactive isotope of iodine has a half-life of eight days. What amount of an 80 gram sample would remain unchanged after 24 days?

• 10 grams

• 20 grams

• 30 grams

• 40 grams

9. Plutonium-238 (Pu-238) decays according to the reaction shown. What is the identity of the radioisotope X?

• 
• 
• 
• 

10. The half-life of a radioactive isotope is the time required for one-half of the initial mass to decay into a different element. The radioactive decay of iodine is shown in the graph. What is the half-life of radioactive iodine?

• 8 days

• 16 days

• 32 days

• 48 days