The order of basicity of amines in the gaseous
phase follows the expected order: tertiary amine > secondary amine
> primary amine > NH3 The trend is not regular in the aqueous
state as evident by their pKb values given in Table 9 3 In the
aqueous phase, the substituted ammonium cations get stabilised
not only by electron releasing effect of the alkyl group (+I) but also
by solvation with water molecules