Question

The missing term in ${}_{+1}^{1}p{+}_{-1}^{0}e⟶{}_0^{1}n+?$, is:

• A. $\gamma$-rays
• B. infrared
• C. X-rays
• D. visible rays

Answer 1

The correct option is C X-rays

Since the proton is changed to a neutron in electron capture, the number of neutrons increases by 1, the number of protons decreases by 1, and the atomic mass number remains unchanged. By changing the number of protons, electron capture transforms the nuclide into a new element. The atom now exists in an excited state with the inner shell missing an electron. While transiting to the ground state, the atom will emit an X-ray photon.