Question

Which of the following are true about esters?

• A. They have a sweet smell.
• B. They are volatile.
• C. They are used to make cough syrups.
• D. They are used in preparation of soaps.

Answer 1

Answer: (A), (B), (D)

The correct options are
A They have a sweet smell.
B They are volatile.
D They are used in preparation of soaps.

Esters are functional groups which are generally represented as R-COO-R', where R and R' are alkyl groups. They are sweet smelling substances which are highly volatile. They are generally used in the manufacture of perfumes. However, in the manufacturing of cough syrups, ethanol is used.
Soaps are prepared by alkaline hydrolysis of esters. The process is known as saponification. In this process the esters react with a base to give back the alcohol and salt of carboxylic acid. For example:

$C{H}_{3}COO{C}_2{H}_5+NaOH\to C{H}_{3}COONa+C_2{H}_{5}OH$