Question

The decay of a proton to neutron is :

• A. not possible, as proton mass is less than the neutron mass.
• B. always possible as it is associated only with ${\beta }^{+}$ decay.
• C. possible only inside the nucleus.
• D. not possible, but neutron to proton conversion is possible.

Answer 1

The correct option is C possible only inside the nucleus.

Positron emission or ${\beta }^{+}$ decay is a type of radioactive decay called $\beta$ decay, in which a proton inside a nucleus is converted into a neutron while releasing a positron and an electron neutrino.
So, decay of a proton to neutron is possible only inside the nucleus.