Question

Distinguish between esterification and saponification reactions of organic compounds.

Answer 1

Hint: In the esterification reactions, esters are produced while in the saponification reactions, soaps are produced. The esterification reaction is mainly the reaction between an acid and an alcohol while saponification reaction mainly uses water and ester salts as the reactants.

Complete Solution :
Esterification reactions and saponification reactions are completely different reactions. Let us understand the difference between these two reactions in a detailed manner.

Esterification	Saponification
In the esterification reaction, a carboxylic acid reacts with an alcohol to form a sweet-smelling compound known as esters.	In the saponification reaction, an ester undergoes alkaline hydrolysis to form a salt of carboxylic acid and an alcohol. As we can see, the saponification reaction is the exact opposite reaction of the esterification reaction.
The esterification reaction takes place in the presence of concentrated sulphuric acid (${ H }_{ 2 }{ SO }_{ 4 }$).	The saponification reaction takes place in the presence of a strong alkali such as sodium hydroxide (NaOH).
An example of esterification reaction is given below.${ CH }_{ 3 }{ COOH }+{ CH }_{ 3 }{ CH }_{ 2 }OH\overset { \text{Conc. }{ H }_{ 2 }{ SO }_{ 4 } }{ \longrightarrow } { CH }_{ 3 }COO{ CH }_{ 2 }{ CH }_{ 3 }+{ H }_{ 2 }O$	An example of saponification reaction is given below.${ CH }_{ 3 }COO{ CH }_{ 2 }{ CH }_{ 3 }+NaOH\overset { {OH}^{-}/H_2O }{ \longrightarrow } { CH }_{ 3 }COONa+{ CH }_{ 3 }{ CH }_{ 2 }OH$

> The saponification reaction is used in the production of soaps. Soaps are the sodium or potassium salts of fatty acids. Fatty acids are the carboxylic acids that have long aliphatic carbon chains. The carbon chains can be saturated or unsaturated (Unsaturated carbon chains have double or triple bonds in it). Usually, the fatty acids have unbranched carbon chains in which the number of carbon atoms is even-numbered from 4 to 28.
An ester of a fatty acid undergoes a saponification reaction to form a soap. An example of soap is sodium stearate. Its chemical formula is ${ C }_{ 17 }{ H }_{ 35 }CO{ O }^{ + }{ Na }^{ - }$.

Note: Always remember that in the saponification reaction, a salt of the carboxylic acid is produced. When the ester is hydrolysed carboxylic acid and alcohol are primarily formed but since an alkali is present in the solution, the carboxylic acid readily reacts with the alkali to undergo neutralisation reaction and forms a salt.