JEE Main 2026 — Alcohols Phenols and Ethers Question with Solution

The chemical reaction of phenol with zinc dust is given by:

$C_6{H}_{5}OH+Zn\stackrel{\Delta }{\to }{C}_6{H}_6+ZnO$

Product X is benzene ($C_6{H}_6$).

Molar mass of phenol ($C_6{H}_{5}OH$) = $6\times 12+6\times 1+16=94$ g mol${}^{-1}$

Number of moles of phenol taken = $\frac{4.7}{94}=0.05$ mol

From the stoichiometry of the reaction, 1 mole of phenol produces 1 mole of benzene.

Theoretical moles of X formed = $0.05$ mol

Since the reaction goes to $60\%$ completion, the actual moles of X formed is:

$0.05\times \frac{60}{100}=0.03$ mol

This can be written as $3\times 10^{-2}$ mol.

Answer: $3$