Question

23) Which among the following is a detergent.

• A. sodium stearate
• B. sodium chloride
• C. sodium carbonate
• D. sodium lauryl sulfate

Answer 1

The correct option is D

sodium lauryl sulfate

Explanation for the correct option -

(D) Sodium lauryl sulfate represented by the molecular formula ${\mathrm{CH}}_3{\left({\mathrm{CH}}_2\right)}_{11}{\mathrm{OSO}}_3\mathrm{Na}$ is a detergent and has the ability to form lather or scum with hard water.

Explanation for the incorrect option -

(A) Sodium stearate is made up of a long chain of carbon (35 carbon atoms) and does not form lather with hard water , hence it is a soap.

(B) Sodium chloride represented by $\mathrm{NaCl}$ is the common salt.

(C ) Sodium carbonate represented by ${\mathrm{Na}}_2{\mathrm{CO}}_3$ is also known as washing soda. It forms carbonic acid when dissolved in water.

Hence, the correct option is (D).