Which is more basic, aliphatic amines or ammonia and why ?

Explanation

Aliphatic amines are stronger bases than ammonia. This can be explain on the basis of the +I effect electron-donating effect of alkyl group attached to the nitrogen atom. This increase the electron density on the nitrogen atom. Thus amines can donate the lone pair of electrons more easily than ammonia.
Moreover, electron releasing effect of alkyl group stabilised the alkyl ammonium ion formed and hence, shifts the equilibrium in the forward direction making the alkyl amines stronger bases than ammonia.