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Following Mass Numbers Through a Decay Chain 4 questions
Following Mass Numbers Through a Decay Chain
Base your answers on the information provided and your knowledge of chemistry. Use the 2025 Chemistry Reference Tables as needed.
A class uses a nuclear simulation that follows one parent through two successive changes. P, I, and D label the parent, intermediate, and final daughter. The display records the mass number A and atomic number Z for each nucleus.
| Nucleus | A | Z |
|---|---|---|
| P | 226 | 88 |
| I | 222 | 86 |
| D | 218 | 84 |
Question 1
Which emitted particle balances the change from P to I?
- A neutron
- An alpha particle
- A beta-minus particle
- A proton
Question 2
Calculate the combined mass number and combined charge number of the particles emitted in the two steps. Use the parent and final daughter values.
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A second display shows the same parent and final daughter but gives the intermediate values as A = 222 and Z = 87. It claims each of the two steps emits one alpha particle.
Question 3
Explain how the intermediate charge number reveals an error even though the parent-to-daughter total remains the same. Use either step.
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Question 4
A corrected record gives 136 neutrons and a mass number of 222 for the intermediate. Calculate its atomic number and identify the element using the periodic table.
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