Final answer:
During the gamma decay of technetium-99m, the nucleus emits a high-energy photon (gamma ray), while the number of protons and neutrons remains unchanged, resulting in no change to the atomic number, mass number, or electron configuration.
Step-by-step explanation:
The question asks about the events that occur during the gamma decay of an atom of technetium-99m (Tc-99m). During gamma decay, the nucleus emits a high-energy photon, known as a gamma ray. This emission does not change the number of protons or neutrons in the nucleus, meaning that the atomic number (Z) and mass number (A) remain unchanged. As a result the atom does not convert into an isotope of a different element. Furthermore since gamma decay involves the nucleus and not the electron cloud, there is no change in the electron configuration of the atom.
Therefore, the correct statements about what will occur during the gamma decay of an atom of technetium-99m are:
- The nucleus will emit a high-energy photon.
- The number of protons and neutrons in the nucleus will be unchanged.
- No change in the electron configuration.
Gamma decay is a process where an excited nucleus releases energy to move to a lower energy state, and in the case of technetium-99m it does so by emitting a gamma ray and transforming into technetium-99 without altering its chemical identity.