Question

Give two reactions that show the acidic nature of phenol. Compare acidity of phenol with that of ethanol.

Answer 1

Two reactions that show the acidic nature of phenol are as follows:
$\left(i\right)$ The reaction of phenol with sodium to form sodium phenoxide with liberation of hydrogen gas.
$C_6{H}_{5}OH+Na\to C_6{H}_5-ONa+\frac{1}{2}{H}_2\uparrow$
(ii) The reaction of phenol with sodium hydroxide to give sodium phenoxide and water.
$C_6{H}_5-OH+NaOH\to C_6{H}_5-ONa+H_{2}O$
Phenol is more acidic than ethanol.
Deprotonation of phenol gives phenoxide ion which is resonance stabilized.
There is no resonance stabilization for the deprotonation of ethoxide ion (obtained by deprotonation of ethanol).