Question

Reduction of nitrobenzene by which of the following reagents gives aniline?
(A) $Sn$ / $HCl$
(B) $Fe$ / $HCl$
(C) ${H_2} - Pd$
(D) $Sn$ / $N{H_4}OH$

Answer 1

Hint : Reduction is the chemical reaction in which one of the atoms involved in a reaction between two chemicals gains electrons. It is also when a substance loses oxygen.

Complete Step By Step Answer:
The organic compound nitrobenzene has the chemical formula ${C_6}{H_5}N{O_2}$ . It is a pale-yellow oil that is insoluble in water and smells like almonds. Greenish-yellow crystals form when it freezes. It is made on a wide scale as a precursor to aniline from benzene. It is sometimes used as a solvent in the laboratory, especially for electrophilic reagents.
The organic compound aniline has the formula ${C_6}{H_5}N{H_2}$ . Aniline is the simplest aromatic amine, consisting of a phenyl group bound to an amino group. It is a versatile starting material for fine chemical synthesis as well as an industrially important commodity chemical.
$Sn$ and concentrated $HCl$ convert nitrobenzene to aniline. We can represent this chemical reaction as follows:
${C_6}{H_5}N{O_2}\xrightarrow[{NaOH}]{{Sn,HCl}}{C_6}{H_5}N{H_2}$
$Fe$ or $Zn$ may be used instead of $Sn$ . This reaction produces aniline salt. The aniline salt is then treated with aqueous $NaOH$ to release the aniline.
Reduction of nitrobenzene by ${H_2} - Pd$ reagent also gives aniline. That is,
${C_6}{H_5}N{O_2}\xrightarrow[{E\operatorname{t} hanol}]{{{H_2} - Pd}}{C_6}{H_5}N{H_2}$
$Sn$ / $N{H_4}OH$ won’t give aniline.
Hence, we found that nitrobenzene converted to aniline by reacting it with the following reagents:
$Sn$ / $HCl$
$Fe$ / $HCl$
${H_2} - Pd$
So, the answer is A, B, and C.

Note :
Benzene is a colorless, transparent liquid that is highly flammable and volatile. The organic compound aniline is a yellowish to brownish oily liquid with a musty fishy odor. Ammonia and phenol extracted from the cumene process can also be used to make aniline.