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CHEMACTIVITY 17B: Decay and Time
POSSIBLE CLICKER QUESTIONS
After CTQ 5:
1. After two half-lives have past, how much of the original material is left?
2. The half-life of thorium-232 is 14 billion years. How long total will it take a 20-g sample of
thorium-232 to decay such that only 5 g thorium-232 remain?
3. For a given isotope, the half-life
4. undergoes beta decay and then the daughter undergoes alpha decay. What is the
final nuclide?
5. As living trees age, the amount of
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6. The amount of in a dead tree
7. The half-life of is 5730 years. A wooden arrow shaft was found to have ¼ of the as
living trees. How old is the arrow?
8. The following is an example of
9. What is the missing product of the following fusion reaction?