Question

Explain why nh3 is basic while bh3 is feebly basic

Answer 1

NH3 is a basic while bh3 is a family basic because nitrogen has a small size due to which The Lone pair of electron is concentrate in a small region this means that the charge density per unit volume is high on moving down a group the size of the central atom increases and the charge get disturb over the electron donating capacity of group 15 element hydride decreases on Mohan down the group

Answer 2

Hey !!

Since the atomic size of N ( 70 pm ) is much smaller then that of Bi ( 148 pm ), electron density on the N-atom is much higher than that of Bi-atom. As a result, the tendency of N in NH₃ to donate its lone pair of electrons is much higher than that of Bi in BiH₃. Thus, NH₃ is much more basic than BiH₃.

Hope it helps you !!