The esters are hydrolyzed in aqueous media, under acid or base catalysis, to yield carboxylic acids and alcohols.

In acidic media, the hydrolysis of esters can be written by the following chemical equation:
 
hydrolysis-acid-esters
 
The mechanism of acid hydrolysis occurs in the following stages:
 
Stage 1. Protonation of the ester
 
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Stage 2. Nucleophilic addition of water to the carbonyl
 
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Stage 3. Acid-base balance, which transforms the methoxide into a good leaving group (methanol).
 
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Stage 4. Elimination of methanol
 
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