Question

Given plausible explanation for each of the following. 

1. Why are amines less acidic than alcohols of comparable molecular masses? 

2. Why do primary amines have higher boiling point than tertiary amines? 

3. Why are aliphatic amines stronger bases than aromatic amines?

Answer 1

1. It is because C₂H₅O° is more stable than C₂H₅NH° because oxygen is more electronegative than nitrogen. 

2. Due to the presence of two H – atoms on N – atom of primary amines, they undergo extensive intennolecular H – bonding while tertiary amines due to the absence of a H – atoms on the N – atom do not undergo H – bonding. As a result, primary amines have higher boiling point than tertiary amines of comparable molecular masses. 

3. It is because there is electron withdrawing, C₆H₅ group in aromatic amines which makes them less basic than aliphatic amines in which alkyl group is electron releasing.