Q.$\text{CH}_3\text{CH}_2\text{CN}$ is reduced with $\text{H}_2/\text{Ni}$ and, separately, $\text{CH}_3\text{NC}$ is reduced with $\text{H}_2/\text{Ni}$. Name the amine product from each reduction and explain why one gives a primary amine and the other gives a secondary amine.

$\text{H}_2/\text{Ni}$ reduces propanenitrile's triple bond fully, turning the nitrile carbon into a $\text{CH}_2\text{NH}_2$ group attached to the rest of the chain: $\text{CH}_3\text{CH}_2\text{CN} + 2\text{H}_2 \xrightarrow{\text{Ni}} \text{CH}_3\text{CH}_2\text{CH}_2\text{NH}_2$ -- a PRIMARY amine, since nitrogen ends up bonded to only one carbon group (the whole propyl chain). $\text{H}_2/\text{Ni}$ reduces methyl isocyanide differently: because nitrogen is already bonded to the methyl group, reduction converts the terminal carbon into a NEW methyl group bonded directly to that same nitrogen: $\text{CH}_3\text{NC} + 2\text{H}_2 \xrightarrow{\text{Ni}} …

Track which atom the new hydrogens attach to in each case -- extending the chain (cyanide) versus adding a second …

Assuming both reductions give the same class of amine just because both start from an $\text{R}-\text{CN}$-type formula -- the cla …