JEE Main · 2025 · 07 Apr 2025 · Shift 2 · Chemical Bonding and Molecular Structure

Hybridisation follows the steric number of the central atom. In sulfur dioxide the sulfur has two bonding regions to oxygen and one lone pair, a steric number of three, so it is $s{p}^2$. In the nitrite ion the central nitrogen likewise has two bonding regions and one lone pair, again steric number three and $s{p}^2$. In the azide ion the central nitrogen has two bonding regions and no lone pair, a steric number of two, so it is $sp$. The hybridisations are thus $s{p}^2$, $s{p}^2$ and $sp$ respectively.