What is the hybridization and geometry of the carbonyl carbon in carboxylic acids and their derivatives?

The carbonyl carbon of carboxylic acids and its derivatives has sp² hybridization and trigonal planar geometry.

Explanation:

Carboxylic acids and its derivatives such as acid chlorides, esters, amides etc, contain a carbonyl group (C=O), in which the carbon atom forms double bond with the oxygen atom. Also, the carbonyl carbon is bonded to two R-groups.

As the carbonyl carbon is bonded to three atoms, thus it has trigonal planar geometry.

In carboxylic acids and it derivatives, the carbonyl carbon is sp² hybridized, as it forms three σ-bonds and one π-bond.

The sp² hybridized carbon is formed by the mixing of the 2s orbital with two 2p orbitals. Whereas, one remaining 2p orbital remains unhybridised.

Therefore, the carbonyl carbon of carboxylic acids and its derivatives has sp² hybridization and trigonal planar geometry.