Question

why anilin is weak base than ethyl amine?

Answer 1

hello your answer is

because
The basic strength is calculated by the availability of lone pairs of electrons on the nitrogen.

Let us compare the availability of lone pair on both the nitrogen in ethyl amine and anilene.

In case of ethyl amine the the ethyl group is showing (+I) effect which is increasing the electron density over the nitrogen .But in case of anilene the electron cloud of nitrogen is conjugately attached to the benzene ring it's attached to . so the availability of electrons is more on ethyl amine. ethyl amine is a stronger base than aniline.