Question

Give reasons for the following observation:

The main product obtained when chloroethane reacts with KCN is propane nitrile while with AgCN it is ethyl isocyanide.

Answer 1

In KCN, the bonding is ionic, which allows the carbon atom of the cyanide ion to be free for bond formation. As a result, propane nitrile is formed.
In contrast, AgCN has covalent bonding, so the carbon atom is not available for bonding. Instead, the nitrogen atom of the cyanide group attacks chloroethane, leading to the formation of ethyl isocyanide.