Is the decay $n \rightarrow e^+ + e^-$ possible considering the appropriate conservation laws? State why or why not.
This is College Physics Answers with Shaun Dychko. Considering the various conservation laws we have, is the decay of a neutron into a positron and electron possible? And the answer is no because if you look up in this table [33.2], the baryon number for a neutron is 1 whereas the baryon number for an electron is 0 and for a positron. So we have 1 on the left for baryon number and 0 in total on the right so the baryon number is not conserved therefore this reaction is not possible.