4.7 g of phenol is heated with Zn to give product X. If this...

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

$C_6H_5OH + Zn \xrightarrow{\Delta} C_6H_6 + ZnO$

Product X is benzene ($C_6H_6$).

Molar mass of phenol ($C_6H_5OH$) = $6 \times 12 + 6 \times 1 + 16 = 94$ g mol$^{-1}$

Number of moles of phenol taken = $\dfrac{4.7}{94} = 0.05$ 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:

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

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

Answer: $3$