The correct order of the basic strength of amines in aqueous medium is

There is a subtle interplay of the inductive effect, solvation effect and steric hindrance of the alkyl group which decides the basic strength of alkylamines in the aqueous medium. The order of basic strength in case of ethyl substituted amines in aqueous solution is as follows (C2H5)2NH > (C2H5)3N> C3H5NH2 > NH3