Question

Write any two methods of preparation of phenol. Give their corresponding equations.

Answer 1

Phenol is an aromatic compound with chemical formula ${C_6}{H_6}O$. It consists of hydroxyl group and phenyl group attached to each other. The two methods of preparation of phenol are Raschig method and Diazotization.

Complete step by step answer:
Phenol is a crystalline solid. Basically it consists of a hydroxyl group and phenol group attached to each other. Moreover, it should be handled with care as it may cause chemical burns.
Now, the method of preparation of this compound are listed below:
$1.$ From diazonium salts (by the hydrolysis of diazonium salt- laboratory method)
So, when a diazonium salt solution is steam distilled or when it is added to boiling dil. ${H_2}S{O_4}$, then phenol is formed. The reaction is as shown:
${C_6}{H_5}{N_2}Cl + {H_2}O\xrightarrow[{{H_2}S{O_4}}]{\Delta }{C_6}{H_5}OH + HCl$
$2.$ From chlorobenzene (Raschig method)
In this process, chlorobenzene is heated with steam at 698K using calcium phosphate or silica as catalyst. Instead, the reaction can be carried out by using water in presence of copper catalyst at 673K. The reaction is a shown:
${C_6}{H_5}Cl + {H_2}O\xrightarrow[{698K}]{{C{a_3}{{(P{O_4})}_2}}}{C_6}{H_5}OH + HCl$

Note: Phenol is so cheap that it attracts plenty of small-scale applications. This compound is a part of industrial paint strippers that are used for the removal of epoxy, polyurethane and other chemically resistant coatings in the aviation industry. Phenol derivatives are used in cosmetic preparation, in hair coloring, exfoliators/skin toners etc.