 The hydrolysis of an ester
also known as saponification is an example of a nucleophilic acyl substitution with the hydroxide ion acting as a nucleophile.In this case the leaving group is an alkoxide ion, which immediately removes a proton from a water molecule to form an alcohol.In the manufacture of soap, sodium chloride is added to salt out the sodium salt of the carboxylic acid; this is an example of the application of the common ion effect.