Question

Number of hydrogen atoms involved in the conversion of nitrobenzene to azobenzene are:

• A. 6
• B. 10
• C. 4
• D. 8

Answer 1

Answer: (D)

8

When nitrobenzene is reduced in an alkaline medium, nitrosobenzene and phenylhydroxylamine are obtained. These intermediates react to form azoxybenzene.
Azoxybenzene on further reduction forms azobenzene and hydrazobenzene.
Reduction of nitrobenzene to nitrosobenzene requires $2H$.
Reduction of nitrobenzene to phenylhydroxylamine requires $4H$.
Reduction of azoxybenzene to azobenzene requires $2H$.
Number of $H$ involved in the conversion of nitrobenzene to azobenzene are $8$.