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Questions
For preparing soap in the laboratory we require an oil and a base. Which of the following combinations of an oil and a base would be best suited for the preparation of soap?
(a) Castor oil and calcium hydroxide
(b) Turpentine oil and sodium hydroxide
(c) Castor oil and sodium hydroxide
(d) Mustard oil and calcium hydroxide
For demonstrating the preparation of soap in the laboratory which of the following combinations of an oil and a base would be most suitable?
(a) Mustard oil and calcium hydroxide
(b) Castor oil and calcium hydroxide
(c) Turpentine oil and sodium hydroxide
(d) Mustard oil and sodium hydroxide
Solution
Soaps are sodium or potassium salt 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, as soap can be prepared by the reaction between sodium hydroxide (NaOH) and turpentine oil (long-chain fatty acid).
Hence, the correct answer is Turpentine oil and sodium hydroxide
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