Radioactivity Quiz

1. Iron-55 is used in medicine to diagnose blood disorders. The half-life of iron-59 is 44.5 days. How much of a 2.0 mg sample will remain after 133.5 days?

• 0.25 mg
• 3 mg
• 25 mg
• 0.5 mg

2. If 10 mg of iodine-131 is given to a patient, how much is left after 24 days? The half-life of iodine-131 is 8 days.

• 1.25 g
• 12.5 mg
• 1.25 mg
• 5 mg

3. Sr-90 decays by alpha decay. What is the new element that is created?

• Krypton-86
• Krypton-90
• Strontium-86
• Strontium- 90

4. If the half-life of iodine-131 is 8.10 days, how long will it take a 50g sample to decay to 6.25g?

• 3 days
• 8.10 days
• 24.3 days
• 2.7 days

5. If Polonium-208 decays by alpha decay, what is the resulting element?

• Lead-204
• Lead-208
• Polonium-208
• Astatine-208

6. What is Half-life?

• The amount of time it takes for some of the nuclei in a sample of the isotope to decay
• The amount of time it takes for half the electrons in a sample of the isotope to decay
• The amount of time it takes for half the nuclei in a sample of the isotope to decay
• The amount of time it takes to double the nuclei in a sample of the isotope to decay

7. The splitting of a nucleus into smaller nuclei is called____.

• isotopes
• half-life
• fusion
• fission

8. Where does fusion occur naturally?

• the sun
• in radioactive waste
• everywhere
• nuclear power plant

9. Lr-256 decays by alpha decay and becomes which of the following:

• Mo-300
• Md- 252
• He-2
• Po-252

10. This type of radioactive decay emits 2 protons and 2 neutrons

• alpha
• beta
• gamma
• delta