AMU Engineering 2019 solved paper Solved Paper

In NH3, the N atom contains one lone pair of electrons and three bond pairs in its valence shell. So, it shows sp3 hybridisation.
Due to presence of one lone pair of electron, its shape deviate from tetrahedral because lone pair shows more repulsion that bond pairs.
As, lp−lp>lp−bp>bp−bp
So, its shape is pyramidal and angle 107°.