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Distinguishing Two Photon Emission Records 4 questions
Distinguishing Two Photon Emission Records
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A display shows two model events in which a photon carries away energy. The source of the photon can be a change inside the nucleus or a change in an electron’s energy. The table tracks which part of each atom changes.
| Event | Nuclear energy | Electron energy | Protons and neutrons |
|---|---|---|---|
| R | Decreases | Unchanged | Unchanged |
| S | Unchanged | Decreases | Unchanged |
Question 1
Which event represents gamma emission from the nucleus?
- R only
- S only
- Both R and S
- Neither R nor S
Question 2
Explain why the nucleus in R keeps both its mass number and atomic number.
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A student sees only the proton and neutron columns for R and concludes that the atom did not emit anything. The full record includes the detected photon.
Question 3
Explain why the unchanged counts can still fit the photon reading.
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Question 4
Another student says any photon emitted by an atom must come from its nucleus. Which record is a counterexample, and what measurement makes it one?
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