Chemistry - GOC Question with Solution | TestHub
A mixture of benzoic acid, 4-methylphenol and naphthalene is dissolved in ether and shaken with aqueous ; the layers are separated. The ether layer is then shaken with aqueous and separated again. The first aqueous layer is acidified with and extracted with ether.
Identify the contents : Flask 1 (aqueous layer from ), Flask 2 (ether layer after ), Flask 3 (ether extract after ), Flask 4 (final aqueous layer).
Options:
Answer:
Solution:
Only the carboxylic acid is strong enough to react with , so it alone enters the first aqueous layer as sodium benzoate; the phenol and the hydrocarbon stay in the ether. 4-Methylphenol is acidic enough to react with ( ≈ 10 vs 15.7), so it passes into the second aqueous layer (Flask 1) as sodium 4-methylphenoxide, leaving naphthalene alone in the ether (Flask 2). Acidifying the first (bicarbonate) layer with reprotonates the carboxylate, and benzoic acid moves into the ether extract (Flask 3), leaving NaCl in the final aqueous layer (Flask 4).
