Answer
See asnwers.
Work Step by Step
Find the difference between the final masses, and the initial mass.
a. $$\Delta m=\left( m(^{232}_{92}U)+ m(^{1}_{0}n)-m(^{233}_{92}U) \right) $$
$$ =\left(232.037156u+1.008665u-233.039636u \right)$$
$$ =0.006185u$$
The final mass is more than the initial mass, so the decay isn’t possible.
b.
$$\Delta m=\left( m(^{13}_{7}N)+ m(^{1}_{0}n)-m(^{14}_{7}N) \right) $$
$$ =\left(13.005739u+1.008665u-14.003074u \right) $$
$$ =0.011330u$$
The final mass is more than the initial mass, so the decay isn’t possible.
c.
$$\Delta m=\left( m(^{39}_{19}K)+ m(^{1}_{0}n)-m(^{40}_{19}K) \right) $$
$$ =\left(38.963706u+1.008665u-39.963998u \right) $$
$$ =0.008373u$$
The final mass is more than the initial mass, so the decay isn’t possible.