An ether solution of benzoic acid, phenol, aniline and naphthalene is extracted first with aqueous NaHCO3, then with aqueous NaOH, then with dilute HCl. The aqueous NaOH extract is separated and acidified with HCl. The organic compound that separates out is

JEE Advanced levelSingle correct optionDifficulty 3 of 3g2128

An ether solution of benzoic acid, phenol, aniline and naphthalene is extracted first with aqueous $NaHCO X_{3}$ , then with aqueous $NaOH$ , then with dilute $HCl$ . The aqueous $NaOH$ extract is separated and acidified with $HCl$ . The organic compound that separates out is

NaHCO X_{3}

(conjugate acid

H X_{2} CO X_{3}

, 6.4) removes only benzoic acid (4.20). The remaining mixture then meets

NaOH

(conjugate acid 15.7), which deprotonates phenol (10.0) to the water-soluble phenoxide; aniline and naphthalene are not acidic. Acidifying the

NaOH

extract regenerates phenol.