The nitration of phenol (and of aniline) is acelerated by the presence of

Options

A. phosphorus acid
B. chlorus acid
C. nitrous acid
D. all of these

Answer

C

Explanation

The nitroso compound is formed first and this is then oxidized to the nitro compound. Thus the fact is used to prepare pure `p-`nitrophenol in very good yield. Phenol is treated with nitrous acid and the product, `p-`nitrosophenol, is oxidized to `p-`nitrophenol.
`HNO_(2) +2H_(2)SO_(4) hArr NO^(+) + H_(3)O^(+) + 22HSO_(4)^(-)`