Ester
A compound formed by replacing the acidic hydrogen of a carboxylic acid with an alkyl group.
Formula / equation
R–COO–R′
Unit
Dimensionless
In depth
Esters cannot donate hydrogen bonds, so they boil lower than the acids and alcohols from which they are made, and they are typically volatile with pleasant fruity odours. They are hydrolysed back by acid or, irreversibly, by alkali in saponification.
Examples in the real world
Ethyl ethanoate as a solvent and nail varnish remover; the triglycerides of fats; aspirin.