Oxidation of phenol with chromic acid produces benzoquinone. In the presence of air, phenols undergo slow oxidation, forming dark-colored mixtures containing quinones.

Heating phenol with zinc dust leads to the conversion of phenol to benzene. Zinc acts as a reducing agent, facilitating this transformation.

The Reimer-Tiemann reaction involves treating phenol with chloroform in the presence of sodium hydroxide, resulting in the introduction of a -CHO group at the ortho position of the benzene ring. The intermediate benzal chloride is hydrolyzed to produce salicylaldehyde.

Methanol is mainly produced through the catalytic hydrogenation of carbon monoxide, utilizing a ZnO – Cr₂O₃ catalyst. It is used as a solvent in paints, varnishes, and predominantly in the production of formaldehyde.

Phenoxide ion, produced by treating phenol with sodium hydroxide, undergoes electrophilic substitution with carbon dioxide in Kolbe’s reaction, forming ortho hydroxybenzoic acid as the main product. The phenoxide ion is more reactive than phenol due to its enhanced nucleophilicity.