Kinetics of Ester Formation via Fischer Esterification

This page is adapted from an existing experiment in the literature (Bromfield-Lee and Oliver-Hoyo, 2009).

In this experiment students explore the time taken for a critical concentration of ester to form when the structures of alcohol and carboxylic acid are varied.


Esters are typically sweet smelling compounds, characterised by the RCOOR’ structure. They are often used in flavourings and perfumes. They also have low boiling points and make good polar solvents.

Image showing the RCOOR' structure of an ester.
General structure of an ester

Fischer Esterification

Fischer Esterification is the esterification of a Carboxylic acid by heating it with an alcohol in the presence of a strong acid catalyst.

Mechanism showing that carboxylic acids react with alcohols to form esters and water. The carbonyl group on the ester originates from the carbonyl group on the carboxylic acid and the O-R' group on the ester originates from the alcohol.
An example of Fischer Esterification

General Experimental Procedure

The way in R groups influence the kinetics of the reaction can be explored by changing EITHER the alcohol or carboxylic acid. This can be done by the following procedure:

  1. Get into small groups
  2. Choose 1 carboxylic acid per group
  3. Mix this with different alcohols in 1:1 ratios in the presence of a few drops of concentrated sulfuric acid. This can be done in a test tube, placed in a hot water bath. Note down the smell of the different esters and the time in which they take to form
  4. Compare the results of the different carboxylic acids between groups and tabulate your findings