2.72.7Esters

FORM 5

A carboxylic acid reacts with alcohol, in the presence of concentrated sulphuric acid (as a catalyst) to form ester and water.

Esters

CH3COOH + CH3OH CH3COOCH3 + H2OEthanoic acid Methanol Methyl ethanoate

C2H5COOH + C3H7OH C2H5COOC3H7 + H2OPropanoic acid Propanol Propyl propanoate

HCOOH + C2H5OH HCOOC2H5 + H2OMethanoic acid Ethanol Ethyl methanoate

C3H7COOH + C3H7OH C3H7COOC3H7 + H2OButanoic acid Propanol Propyl butanoate

CH3COOH + C5H11OH CH3COOC5H11 + H2OEthanoic acid Pentanol Pentyl ethanoate

C4H9COOH + C4H9OH C4H9COOC4H9 + H2OPentanoic acid Butanol Butyl pentanoate

Examples of esters

Uses of esters

Food flavourings

Perfumes

Solvent for glue

Making Soap

Natural sources of esters

FlowersLavender

RoseSun flower

Fruits

PeachEthyl

butanoateC3H7COOC2H5

PineappleEthyl

butanoateC3H7COOC2H5

OrangesOctyl

ethanoatCH3COOC8H17

Oils from plants