The decay of a proton to neutron is: (a) always possible as it is associated only with β + decay (b) possible only inside the nucleus (c) not possible as proton mass is less than the neutron mass (d) not possible but neutron to proton conversation is possible

Answer: (b). p → n + e⁺ + ν needs energy, since mp < mn. Inside a nucleus the extra energy comes from the nuclear binding energy, which is why β⁺ decay occurs. A free proton cannot do this. So the answer is (b) possible only inside the nucleus.

The decay of a proton to neutron is: | JEE Main 2021 (18 Mar, Shift 2)

Q17JEE Main 2021 · 18 MAR · SHIFT 2Easy

Radioactive Decays: Alpha, Beta, Gamma

The decay of a proton to neutron is:

Show answer and solution

Answer: (b)

$p \to n + e^+ + \nu$ needs energy, since $m_p < m_n$ .
Inside a nucleus the extra energy comes from the nuclear binding energy, which is why $\beta^+$ decay occurs.
A free proton cannot do this.
So the answer is (b) possible only inside the nucleus.

Report a mistake

Radioactive Decays: Alpha, Beta, Gamma question from JEE Main 2021 (18 Mar, Shift 2)

More questions on Radioactive Decays: Alpha, Beta, Gamma