Phenols are a type of organic compound containing a hydroxyl, -OH, functional group directly bonded to an aromatic ring.

The formula of phenol is C₆H₅OH.

The skeletal formula of phenol is:

React both with a metal carbonate such as sodium carbonate.

The carboxylic acid will react to produce carbon dioxide, which is evolved as a gas. Phenol is not acidic enough to react.

Phenol reacts with sodium hydroxide to form the salt, sodium phenoxide, and water in a neutralisation reaction.

C₆H₅OH + NaOH ➔ C₆H₅ONa + H₂O

Phenol neutralises other alkalis in the same way to form a salt and water.

Phenol reacts with an aqueous solution of bromine at room temperature to form a white precipitate of 2,4,6-tribromophenol. The reaction decolourises the bromine water.

In contrast to benzene, the halogenation of phenol does not require a halogen carrier.

Phenol reacts readily with dilute nitric acid at room temperature to form a mixture of 2-nitrophenol and 4-nitrophenol.

The lone pairs of electrons on the oxygen atom of the -OH group in phenol are donated into its π-system. This activates phenol's aromatic ring, making it more susceptible to electrophilic attack.

Phenol is nitrated with dilute nitric acid whereas benzene requires concentrated nitric and sulfuric acids.

Phenol is more reactive than benzene.

A lone pair of electrons from the oxygen p-orbital of the -OH group is donated into the π-system of phenol, increasing the electron density of the benzene ring, which attracts electrophiles more strongly compared to benzene.