The hybridisation of the nitrogen atom in ammonia is
- A. sp3, with the lone pair occupying one of the four hybrid orbitals
- B. sp2
- C. sp
- D. unhybridised
Explanation
Nitrogen has four regions of electron density, three bonds and one lone pair, so four sp3 hybrids are needed even though only three of them are used for bonding. This is why the observed angle of 107 degrees is close to the tetrahedral value rather than to 120 degrees. Lone pairs must always be counted when deciding hybridisation.