Question

Assertion: Transparent soaps are made by dissolving soaps in ethanol
Reason: Ethanol makes things invisible

A.) Both assertion and reason are correct and reason is the correct explanation for assertion.
B.) Both assertion and reason are correct but reason is NOT the correct explanation for assertion.
C.) Both assertion and reason are incorrect
D.) Assertion is correct but reason is incorrect
E.) Assertion is incorrect but reason is correct.

Answer 1

Hint: Soaps are sodium or potassium fatty acids salts, produced from the hydrolysis of fats in a chemical reaction called saponification. Each soap molecule has a long hydrocarbon chain, sometimes called its 'tail', with a carboxylate 'head'.

Complete step by step answer:
Let us first understand how soaps are formed!
So, in very simple words, Soap is formed when organic acid reacts with caustic soda or sodium hydroxide or potassium hydroxide. Saponification is a chemical process by which triglycerides (fatty acids) are reacted with sodium hydroxide to produce glycerol and a fatty acid salt called ‘soap’. These fatty acids are more often animal fats or vegetable oils.

Now, let us consider the question.
Transparent soaps are made by dissolving the soap in ethanol and then evaporating the excess solvent. Here we use ethanol to prepare transparent soaps because water and oil are unable to mix, therefore ethanol has the ability to dissolve on a partial level in water and oil. But it is wrong to say that ethanol makes things visible.

Hence, Assertion is correct but reason is incorrect. Option D is the required answer.

Note: Saponification is important to the industrial user to know the amount of free fatty acid present, since this determines in large measure the refining loss. Therefore, saponification is important.