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Separating Photon Counts From Decay Counts 4 questions
Separating Photon Counts From Decay Counts
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A classroom nuclear simulation compares two model parents. Each decay of X emits two photons and each decay of Y emits one. Each photon reaching the first detector contributes one count. The detector records every photon in this model.
| Parent sample | Photon counts during the same interval |
|---|---|
| X | 64 |
| Y | 32 |
Question 1
How many X nuclei decayed during the interval?
- 16
- 32
- 64
- 128
Question 2
A student concludes that twice as many X nuclei decayed because X gave twice as many counts. Evaluate the claim using both emission rules.
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A second detector can group all photons from one decay into one event. Assume it detects both samples completely and groups them correctly.
Question 3
Predict the event readings for both samples over that same interval. Explain why the count comparison changes.
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Question 4
Explain why equal event readings over one interval still do not establish that X and Y have the same half-life.
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