Question

Which of the following represents the saponification reaction?

• A. ${\mathrm{CH}}_3\mathrm{COONa}+\mathrm{NaOH}\to {\mathrm{CH}}_4+{\mathrm{Na}}_2{\mathrm{CO}}_3$
• B. ${\mathrm{CH}}_3\mathrm{COOH}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\to {\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5+{\mathrm{H}}_2$
• C. $2{\mathrm{CH}}_3\mathrm{COOH}+2\mathrm{Na}\to 2{\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{H}}_2$
• D. ${\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5+\mathrm{NaOH}\to {\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

Answer 1

The correct option is D

${\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5+\mathrm{NaOH}\to {\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

Explanation for correct option:

D. ${\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5+\mathrm{NaOH}\to {\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

Saponification reaction:

• When an ester reacts with a base, it yields carboxylate salt and alcohol. This can be also known as Ester hydrolysis with a base.
• It is also known as saponification reaction, i.e. it is used to synthesize soap.
• For example, when ethyl acetate$\left({\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5\right)$ is treated with sodium hydroxide$\left(\mathrm{NaOH}\right)$, it produces sodium acetate$\left({\mathrm{CH}}_3\mathrm{COONa}\right)$ and ethanol$\left({\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\right)$.
• The chemical reaction can be depicted as:

${\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5\left(\mathrm{aq}\right)+\mathrm{NaOH}\left(\mathrm{aq}\right)\to {\mathrm{CH}}_3\mathrm{COONa}\left(\mathrm{aq}\right)+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\left(\mathrm{aq}\right)$

Explanation for incorrect options:

A. ${\mathrm{CH}}_3\mathrm{COONa}+\mathrm{NaOH}\to {\mathrm{CH}}_4+{\mathrm{Na}}_2{\mathrm{CO}}_3$

• This is a reaction when a mixture of soda-lime and sodium acetate is heated.

B. ${\mathrm{CH}}_3\mathrm{COOH}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}\to {\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5+{\mathrm{H}}_2$

• This reaction is known as the esterification reaction, as an ester is being produced by reacting an acid with an alcohol.

C. $2{\mathrm{CH}}_3\mathrm{COOH}+2\mathrm{Na}\to 2{\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{H}}_2$

• This is the reaction to the formation of sodium acetate.

Hence, the correct option is D i.e.${\mathrm{CH}}_3{\mathrm{COOC}}_2{\mathrm{H}}_5+\mathrm{NaOH}\to {\mathrm{CH}}_3\mathrm{COONa}+{\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$ represents saponification reaction.