Question

an article about half-lives describes a parent isotope. what is a parent isotope? the isotope that forms from the radioactive decay of a less stable isotope the isotope that forms from the radioactive decay of a more stable isotope an isotope that undergoes radioactive decay to form a less stable isotope an isotope that undergoes radioactive decay to form a more stable isotope

Explanation:

1. Recall the concept of parent and daughter isotopes in radioactive decay: A parent isotope is the one that decays (undergoes radioactive decay).
2. Radioactive decay occurs because the parent isotope is less stable, and it decays to form a daughter isotope which is more stable (since the process of decay is towards a more stable nuclear configuration).
3. Analyze the options:

• Option A and B describe a daughter isotope (formed from decay), not parent.
• Option C says it forms a less stable isotope, which is incorrect as decay leads to more stability.
• Option D correctly states that a parent isotope undergoes decay to form a more stable isotope.

Answer:

D. an isotope that undergoes radioactive decay to form a more stable isotope