250+ TOP MCQs on Uses of Carboxylic Acids and Answers

Chemistry Multiple Choice Questions on “Uses of Carboxylic Acids”.

1. Which of the following is not a use of methanoic acid?
a) Leather tanning
b) Coagulant in rubber industry
c) Food preservative
d) Textile dyeing
Answer: c
Clarification: Methanoic acid is the simplest acid and is used in rubber manufacturing, leather tanning, textile dyeing and finishing and electroplating industries.

2. Which carboxylic acid is used in the manufacturing of nylon-6,6?
a) Propanedioic acid
b) Butanedioic acid
c) Pentanedioic acid
d) Hexanedioic acid
Answer: d
Clarification: Nylon-6,6 is manufactured from the condensation polymerisation of hexanedioic acid (adipic acid) with hexamethylenediamine under high pressure and temperature.

3. Esters of which acid are used in the perfume industry?
a) Ethanoic acid
b) Benzoic acid
c) Phthalic acid
d) Formic acid
Answer: b
Clarification: Esters of benzoic acids are used in the perfumery industry. For example, ethyl benzoate is a component of some fragrances and artificial flavours.

4. __________ is commonly used as a food preservative.
a) Sodium benzoate
b) Potassium benzoate
c) Terephthalic acid
d) Acetic acid
Answer: a
Clarification: When C₆H₅COOH reacts with NaOH, a salt called sodium benzoate is formed. When an aqueous salt solution is prepared from this product, it acts as a preservative. It is identified by the code E211.

5. Which of the following carboxylic acids is not used in the manufacturing of soaps?
a) Capric acid
b) Stearic acid
c) Oleic acid
d) Palmitic acid
Answer: a
Clarification: Soaps are sodium or potassium salts of long chain fatty acids like stearic, oleic, palmitic acids, etc. Capric acid is decanoic acid and contains 10 carbon atoms and is not classified as a fatty acid.

6. Ethanoic acid is used as vinegar in the cooking industry.
a) True
b) False
Answer: a
Clarification: Generally, a 1:10 solution of acetic acid in water is called vinegar. It is a commercial product that may be used in salads or other foods. It may include traces of other chemicals for the need of flavouring.