Question

Choose the statement which best describe ester :

Statement 1: Ester is formed due to the reaction between ethanol and Ethanoic acid.

Statement 2: Esters are sweet smelling substances.

Statement 3: Ester are formed due to the reaction between an acid and a carboxylic acid.

Statement 4: On treating with sodium hydroxide, ester is converted back to alcohol and sodium salt of carboxylic acid.

Statement 5: Preparation of soap involves treating sodium hydroxide with ester.

• A. Statement 1 is correct
• B. Statements 1, 2, 4 and 5 are correct.
• C. Only statement 3 is correct
• D. Only statements 1, 2 and 5 are correct

Answer 1

The correct option is B

Statements 1, 2, 4 and 5 are correct.

Esters are formed by the reaction of an acid and an alcohol. Ethanoic acid reacts with absolute ethanol in the presence of an acid catalyst to give an ester.

$C{H}_{3}COOH$ + $C{H}_{3}C{H}_{2}OH$ + Acid Catalyst $\to$ $C{H}_{3}COOC{H}_{2}C{H}_3$

Esters are sweet smelling substances. These are used in making perfumes and as flavouring agents. On treating with sodium hydroxide, which is an alkali, the ester is converted back to alcohol and sodium salt of carboxylic acid. This reaction is known as saponification because it is used in the preparation of soap.

Hence, statements 1, 2, 4 and 5 correctly describes Ester.