Final answer:
The mixture of benzoic acid and naphthalene can indeed be separated using benzene, but the solubility of benzoic acid in hot water is not the reason why this method is effective. Option A is correct answer.
Step-by-step explanation:
The student asks about the separation of a mixture containing benzoic acid and naphthalene using benzene and whether the fact that benzoic acid is soluble in hot water is relevant to the separation process. Assertion A states that benzoic acid can be separated out by the use of benzene, which is true because benzoic acid is not readily soluble in water, but is soluble in benzene.
However, Reason R, which mentions benzoic acid being soluble in hot water, is not the correct explanation for Assertion A since this property is not directly related to the use of benzene for the separation.
Based on the properties of naphthalene and benzoic acid, we know that naphthalene is a nonpolar compound with only London dispersion forces, leading to low solubility in water. In contrast, benzoic acid has a polar carboxyl group but is less soluble than LiCl (which is an ionic compound) in water due to the presence of a nonpolar aromatic ring. The separation by benzene capitalizes on the solubility of benzoic acid in nonpolar solvents like benzene rather than its solubility in hot water.
The correct answer in this case is option A: Both A and R are true but R is NOT the correct explanation of A. The solubility of benzoic acid in hot water is not relevant to the extraction of benzoic acid using benzene.