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Following a Daughter After the Parent Is Gone 4 questions
Following a Daughter After the Parent Is Gone
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A nuclear simulation has parent P and unstable daughter D. Over one model interval, half of the D nuclei present at the start decay. While the parent source is enabled, it adds new D nuclei at the end of the interval. The event counter in this case counts only D decays.
| Source during the second interval | D at start of that interval | New D added at its end |
|---|---|---|
| P, parent source stays on | 20 | 10 |
| Q, parent source turns off | 20 | 0 |
Question 1
How many D decays occur in each trial during the second interval?
- P gives ten and Q gives zero.
- Both give ten.
- P gives twenty and Q gives ten.
- Both give zero.
Question 2
Calculate the D count at the end of the second interval for each source schedule.
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Question 3
A student uses the second interval’s daughter decay count to identify which source is still on. Explain why that evidence is insufficient.
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Each source keeps its second-interval setting for a third interval. The same decay rule applies.
Question 4
Compare the expected daughter decay counts in the third interval. Explain how these readings help distinguish the source schedules.
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