Esters are named using the suffix -oate.

The names of esters are based on the parent carboxylic acid. The first part of the name comes from the alkyl or aryl group that has replaced the hydrogen of the acid. The second part of the name comes from the name of the parent acid, with the ending changed to -oate.

For example, methyl ethanoate comes from ethanoic acid, with the hydrogen of the acid replaced by a methyl group:

Esters have the functional group -COO-.

Esters are produced from carboxylic acids through a process called esterification. In this process, an alcohol is warmed with a carboxylic acid in the presence of a small amount of concentrated sulfuric acid, which acts as a catalyst. The result is an ester and water.

Alcohol + carboxylic acid ⇌ ester + water

Esters are typically used in flavourings and perfumes due to their pleasant smells. They are also used as solvents and plasticisers.

In acid hydrolysis, the ester is heated under reflux with dilute aqueous acid. The ester is broken down by water, with the acid acting as a catalyst. The products of acid hydrolysis are a carboxylic acid and an alcohol.

Ester + water ⇌ carboxylic acid + alcohol

In alkaline hydrolysis, also known as saponification, the ester is heated under reflux with aqueous hydroxide ions. The products of alkaline hydrolysis are a carboxylate salt and an alcohol.   

Ester + alkali ➔ carboxylate salt + alcohol

Animal fats and vegetable oils are esters (of glycerol).

Glycerol is also called propane-1,2,3-diol.

A triglyceride consists of a glycerol molecule (propane-1,2,3-triol), combined with three fatty acid molecules (long chain carboxylic acids). The general structure of a triglyceride is shown below.

Animal fats and vegetable oils are examples of triglycerides.

At room temperature, fats are solid and oils are liquid.

Fats contain saturated fatty acids which can pack closely together; this leads to strong intermolecular forces between chains which require a lot of energy to overcome.

In contrast, oils contain unsaturated fatty acids which can't pack together as the C=C bond causes a bend in the chain. This leads to weaker intermolecular forces between chains which require less energy to overcome.

A soap is a salt of a long chain carboxylic acid.

A soap is typically a sodium salt of a fatty acid.

Soaps are made by boiling fats or oils with a strong alkali solution. This process is called saponification. It breaks the ester bonds joining the fatty acids to the glycerol, releasing the fatty acids which then combine with the alkali to form soap.

Because it comes from crops that can be replanted and reproduced.

Biodiesel is a mixture of methyl esters of long chain fatty acids derived from vegetable oils or animal fats.

Biodiesel is produced by reacting oils or fats with methanol in the presence of a catalyst. The triglyceride molecules in the oils/fats are broken down into glycerol and fatty acid methyl esters which make up the biodiesel fuel. The glycerol is removed as a byproduct.