Question

State True or False.

The geometry of $N{H}_3$ and $B{H}_3$ is same.

• A. True
• B. False

Answer 1

The correct option is B False

The given statement is False.
The geometry of $N{H}_3$ is different from the geometry of $B{H}_3$. The central N atom in $N{H}_3$ molecule is $s{p}^3$ hybridised with one lone pair and 3 bond pairs of electrons. The electron pair geometry is tetrahedral and molecular geometry is pyramidal. In $B{H}_3$, the central B atom has 3 bond pairs of electrons and 0 lone pairs of electrons. It forms dimer $B_2{H}_6$ which involves $s{p}^3$ hybridisation of B atom and $3c-2e$ $B-H-B$ bridges (called banana bonds) and terminal $B-H$ bonds which are $2c-2e$ bonds.