Question

Which of the following reactions are not possible?

• A. p $\to$ n+ positron + energy
• B. n $\to$ p+ electron + energy
• C. ${}_{13}A{L}^{27}{+}_{1}H{I}^2{\to }_{12}M{g}^{25}{+}_{2}H{e}^4$
• D. ${}_{92}{U}^{235}{+}_0{n}^1{\to }_{54}X{e}^{140}{+}_{38}S{r}^{95}+2_0{n}^1+\gamma$

Answer 1

The correct option is A p $\to$ n+ positron + energy

In particle physics, proton decay is a hypothetical form of radioactive decay in which the proton decays into lighter subatomic particles, such as a neutral pion and positron. There is currently no experimental evidence that proton decay occurs.

So, option $\left(A\right)$ is incorrect because there is no experimental evidence but there is experimental evidence of decay of neutron.