Explanation

(d)
[image:13_image194.emf](2${^\circ}$amine) is strongest base. Basic nature of amines due to presence of lone pair of electron on nitrogen atom which is available for the bond formation with Lewis acid. Due to the +I effect 2${^\circ}$ amine is better base than 1${^\circ}$ amine and $NH_{3}$. In case of aromatic amines the lone pair on nitrogen atom involved in resonance, therefore, not available for bond formation, so aromatic amines are less basic.