2.4 - Esters, Fats and Oils

Esters, Fats and Oils

Higher Chemistry 2.4

Esters have the ester link as their functional group (-COO). 

Esters are formed by a condensation reaction between carboxylic acids and alcohols. It is a reversible reaction. To make an ester, the hydrogen atom must be removed from the hydroxyl group. The -OH must be removed from the acid's carboxyl group. The hydrogen and the -OH merge and form water.

Esters can also undergo hydrolysis to form the alcohol and carboxylic acid used to make it. This is achieved by heating the ester with an alkali.

Naming esters

1. Change the name of the alcohol to end in -yl (ie propanol to propyl)

2. Change the name of the acid to end in -oate (ie ethanoic acid to ethanoate)

3. The alcohol is the first part of the name and the acid is the second part (ie propyl ethanoate)

Esters that are produced from alcohols and carboxylic acids that have the same total number of carbon atoms will have the same molecular formula and will be isomers of each other.

As esters increase in size, their boiling point increases. Esters are non-polar and are unable to dissolve in water…