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How will you bring about the following conversion?
Phenol from benzene sulphonic acid
Answer
Answer
Official answer keyEquations: $\mathrm{C_{6}H_{5}SO_{3}H} + \mathrm{NaOH} \longrightarrow \mathrm{C_{6}H_{5}SO_{3}Na} + \mathrm{H_{2}O}$ $\mathrm{C_{6}H_{5}SO_{3}Na} + 2\mathrm{NaOH} \xrightarrow{\text{NaOH}\text{,}\text{ }\text{573-623}\text{ }\text{K}} \mathrm{C_{6}H_{5}ONa} + \mathrm{Na_{2}SO_{3}} + \mathrm{H_{2}O}$ $\mathrm{C_{6}H_{5}ONa} + \mathrm{HCl} \longrightarrow \mathrm{C_{6}H_{5}OH} + \mathrm{NaCl}$
Benzenesulphonic acid is neutralised, fused with NaOH at 573-623 K to give sodium phenoxide, then acidified with HCl.
From ISC 2026 Specimen Chemistry Paper 1, question 12(i).