Phenol reacts with a compound (X) in the presence of aq. NaOH to produce phenyl benzoate. Identify (X). 

Benzoyl chloride 

The correct answer is option 2. Benzoyl chloride.

Phenol reacts with a compound \(X\) in the presence of aqueous NaOH to produce phenyl benzoate. This reaction is a typical example of the Schotten-Baumann reaction, which involves the formation of an ester from a phenol and an acid chloride.

Schotten-Baumann Reaction Mechanism:

Phenol Deprotonation:

Phenol \((C_6H_5OH)\) is deprotonated by aqueous NaOH to form the phenoxide ion \((C_6H_5O^-)\)

Nucleophilic Attack:

The phenoxide ion then acts as a nucleophile and attacks the carbonyl carbon of benzoyl chloride \((C_6H_5COCl)\), which is an acyl chloride. This leads to the formation of phenyl benzoate and hydrochloric acid \((HCl)\).

The compound \(X\) that reacts with phenol in the presence of aqueous NaOH to produce phenyl benzoate is benzoyl chloride. Thus, the correct answer is Benzoyl chloride.