(a and b) Primary amines : (i) $\underset{\text{Butanamine}}{\mathrm{CH_3CH_2 CH_2 CH_2 NH_2}}$ (ii) $\underset{\text{Butan-2-amine}}{\mathrm{CH_3CH_2-}\underset{\underset{\mathrm{C}}{\underset{\mathrm{NH}_3}{\vert}}}{\mathrm{H}}\mathrm{-CH_3}}$ (iii) $\underset{\text{2-Methylpropan-2-amine}}{\mathrm{CH_3-}\overset{\overset{\mathrm{CH}_3}{\vert}}{\underset{\underset{\mathrm{CH}_3}{\vert}}{\mathrm{C}}}\mathrm{-NH_2}}$ (iv) $\underset{\text{2-Methylpropan-1-amine}}{\mathrm{CH_3-}\overset{\vert^{\mathrm{CH}_3}\mathrm{C}}{\mathrm{H}}\mathrm{-CH_2-NH_2}}$ (v) $\underset{\text{N-Ethylethanamine}}{\mathrm{CH_3CH_2-NH-CH_2CH_3}}$ (vi) $\underset{\text{N-Methylpropanamine}}{\mathrm{CH_3CH_2CH_2-NH-CH_3}}$ (vii) $\underset{\text{N-Methylpropan-2-amine}}{\mathrm{CH_3-}\overset{\vert^{\mathrm{CH}_3}\mathrm{C}}{\mathrm{H}}\mathrm{-NH-CH_3}}$ Tertiary amine: (viii) $\underset{\text{N, N -Dimethylethanamine}}{\mathrm{CH_3-}\overset{\vert^{\mathrm{CH}_3}}{\mathrm{N}}\mathrm{-CH_2CH_3}}$ (c) Chain isomers : (i) & (iv), (ii) & (iii), (i) & (iii), (ii) & (iv) Position isomers : (i) & (ii), (vi) & (vii) Metamers : (v) & (vi), (v) & (vii) Functional isomers: All primary amines are functional isomers of secondary and tertiary amines and vice versa.