Chemistry - AMINES Question with Solution | TestHub

$\underset{\text{n-butylamine }\left(\text{primary amine}\right)}{{\mathrm{H}}_3\mathrm{C}-\mathrm{C}{\mathrm{H}}_2-\mathrm{C}{\mathrm{H}}_2-\mathrm{C}{\mathrm{H}}_2-\mathrm{N}{\mathrm{H}}_2}$

$\underset{\text{Diethylamine }\left(\text{Secondary amine}\right)}{\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2-\mathrm{N}\mathrm{H}-\mathrm{C}{\mathrm{H}}_2-\mathrm{C}{\mathrm{H}}_3}$

$\underset{\text{ethyldimethylamine }\left(\text{tertiary amine}\right)}{\mathrm{C}{\mathrm{H}}_3-\stackrel{\mathrm{C}{\mathrm{H}}_3}{\stackrel{|}{\mathrm{N}}-{\mathrm{C}}_2{\mathrm{H}}_5}}$

Primary amines have two hydrogen atoms available for hydrogen bond formation, while$2°$amines have only one hydrogen atom for hydrogen bond formation.$3°$amines do not have intermolecular association due to absence of hydrogen atom.

Thus, order of boiling point of isomeric amines is as follows

$3°<2°<1°$

or$\mathrm{I}\mathrm{I}\mathrm{I}<\mathrm{I}\mathrm{I}<\mathrm{I}$.