Write the preparation method of nitro benzene. Explain any three reduction properties of nitrobenzene with equation.

Preparation of Nitrobenzene:
Nitrobenzene is typically prepared through the nitration of benzene, which involves the introduction of a nitro group (-NO2) into the benzene ring. This reaction is carried out using a mixture of concentrated nitric acid (HNO3) and concentrated sulfuric acid (H2SO4) as the nitrating agent. Here's the preparation method:

Materials Needed:

Benzene (C6H6)
Concentrated nitric acid (HNO3)
Concentrated sulfuric acid (H2SO4)
Ice or a cooling bath
Procedure:

Set up a reaction flask, usually made of glass, and place it in a cooling bath filled with ice or chilled water to maintain a low temperature throughout the reaction.

Slowly add concentrated sulfuric acid (H2SO4) to the reaction flask. The sulfuric acid serves as a catalyst and also helps in the formation of the nitronium ion (NO2+), which is the electrophile responsible for the nitration reaction.

Carefully add benzene (C6H6) to the reaction flask. Ensure that you maintain a low temperature throughout the addition to prevent excessive heating.

Slowly add concentrated nitric acid (HNO3) to the reaction flask while stirring the mixture gently. This step should be done gradually and cautiously to control the reaction rate and avoid excessive heat generation.

Continue stirring the reaction mixture for a specific duration, typically a few hours, while maintaining the low temperature.

After the reaction is complete, carefully pour the reaction mixture into a separating funnel containing water. This step will separate the organic layer (containing nitrobenzene) from the aqueous layer.

Collect the organic layer, which is the upper layer, and wash it with water to remove any remaining acid. The product, nitrobenzene, can be isolated through various purification methods, such as distillation or recrystallization.

Reduction Properties of Nitrobenzene:
Nitrobenzene can undergo various reduction reactions, leading to the formation of different compounds. Here are three reduction properties of nitrobenzene along with the corresponding equations:

Reduction to Aniline:
Nitrobenzene can be reduced to form aniline (phenylamine) in the presence of a reducing agent like iron and hydrochloric acid (HCl).

Equation:
C6H5NO2 + 6H2 + 6HCl → C6H5NH2 + 6H2O

Reduction to Nitrosobenzene:
Nitrobenzene can also be reduced to nitrosobenzene (phenylnitroso) using reducing agents such as tin and hydrochloric acid (HCl).

Equation:
C6H5NO2 + 2Sn + 4HCl → C6H5NO + 2SnCl2 + 2H2O

Reduction to Azo Compounds:
In the presence of strong reducing agents like zinc dust and concentrated hydrochloric acid (HCl), nitrobenzene can be reduced to azo compounds.

Equation:
C6H5NO2 + 4Zn + 10HCl → C6H5N2Cl2 + 4ZnCl2 + 5H2O

These reduction reactions demonstrate the versatility of nitrobenzene as a starting material for the synthesis of various organic compounds with different functional groups.