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Checking a Parent and Daughter Age Model 4 questions
Checking a Parent and Daughter Age Model
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A mineral display uses a classroom decay simulation. Each parent nucleus that decays produces one stable daughter nucleus. No nuclei enter or leave the grain. The simulation initially assumes the grain contained parent nuclei only.
| Quantity measured now | Number of nuclei in the model |
|---|---|
| Parent | 24 |
| Daughter | 72 |
Question 1
Under the initial assumption, calculate the original parent count. Show how the daughter count enters your calculation.
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Question 2
How many half-lives have passed under that assumption?
- One half-life
- Two half-lives
- Three half-lives
- Four half-lives
A second model allows 48 of the measured daughter nuclei to have been present from the start. The final measurements remain 24 parents and 72 daughters.
Question 3
Use the revised model to calculate the original parent count and the number of half-lives elapsed.
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Question 4
Explain why assigning every daughter nucleus to decay would give an age that is too large under the revised model.
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