Question

Arrange this in the order of property indicated: NH3, PH3, AsH3, SbH3, BiH3 : Increasing base strength.

Answer 1

On moving down the group from N to **, the atomic size increases, consequently the electron density on the central atom decreases and the basic strength decreases. Therefore, the increasing order of basic strength is as follow : BiH3 < SbH3 < AsH3 < PH3 < NH3