Class 11 NEET Chemistry Chemical Bonding And Molecular Structure Part 1

No. of electron pairs at the central atom
= No. of atoms bonded to it +1/ 2[ Group number of central atom - Valency of the central atom ± no. of electrons ]
No. of electron pairs at the central atom in NO3−
=3+

1

2

[5−6+1]=3      (sp2 hybridisation)
No. of electron pairs at the central atom in H3O+
3+

1

2

[6−3−1]=4        (sp3 hybridisation)