Hydrazobenzene can be obtained from nitro benzene in the presence of:

• (A) Zn + KOH
• (B) Zn + HCl
• (C) Zn + ZnO
• (D) Zn + H₂SO₄

Hydrazobenzene can be synthesized from nitrobenzene through a reduction process. The correct choice for this reaction is:

Reduction Method

The appropriate reducing agent for converting nitrobenzene to hydrazobenzene is:

• (A) Zn + KOH

Why This Choice Works

In this reaction, zinc acts as a reducing agent, and potassium hydroxide provides an alkaline environment that facilitates the reduction of the nitro group to an amine, ultimately leading to the formation of hydrazobenzene.

Other Options Explained

• (B) Zn + HCl - This combination typically leads to the formation of zinc chloride and does not effectively reduce nitrobenzene.
• (C) Zn + ZnO - This is not a suitable reducing environment for this specific transformation.
• (D) Zn + H₂SO₄ - While zinc can reduce in acidic conditions, it is not the best choice for this reaction.

Thus, the most effective method for obtaining hydrazobenzene from nitrobenzene is using zinc in the presence of potassium hydroxide.