Question

Which one of the following sets of materials can be used to prepare soap? 

(A) Neem oil and calcium hydroxide

(B) Castor oil and sodium hydroxide

(C) Mineral oil and sodium hydroxide

(D) Neem oil and magnesium hydroxide

Answer 1

Soaps are sodium or potassium salts of long-chain fatty acids. They are prepared by the reaction of a long-chain fatty acid with either NaOH or KOH. This reaction is known as the saponification reaction. Among the given sets of materials, a soap can be prepared by the reaction between castor oil (long-chain fatty acid) and sodium hydroxide (NaOH).

Hence, the correct answer is option (B).