A nucleus undergoes radioactive decay, emitting a gamma ray. Which of the following statements is true?
A) The daughter nucleus has more neutrons than the parent.
B) A nuclear proton changes into an electron-positron pair.
C) Both daughter and parent nuclei have the same atomic number.
D) The daughter nucleus is more massive than the parent.

Question

Quizplus · Accepted Answer

In gamma decay, the nucleus emits a high-energy photon (gamma ray) without changing its atomic mass or atomic number. This means that the parent and daughter nuclei have the same atomic number. Option A is incorrect because the number of neutrons in the nucleus usually changes during other types of radioactive decay such as alpha or beta decay. Option B is incorrect because gamma decay does not involve a change in nuclear protons or electrons. Option D is incorrect because the mass number (total number of protons and neutrons) of the parent and daughter nuclei remains the same in gamma decay.

A Nucleus Undergoes Radioactive Decay, Emitting a Gamma Ray