In acid medium nitrobenzene is reduced to aniline as shown in the reaction
`C_6H_5-NO_2+6[H]rarrC_6H_5-NH_2+2H_2O` The reducing agent used in this reaction is…

Options

A. `LiAlH_(4)`
B. `Sn//HCl`
C. `Na`/ alcohol
D. `H_(2)//Ni`

Answer

To solve the question regarding the reduction of nitrobenzene to aniline in acid medium, we can follow these steps:

### Step 1: Understand the Reaction
The reaction given is:
\[ C_6H_5-NO_2 + 6[H] \rightarrow C_6H_5-NH_2 + 2H_2O \]
This indicates that nitrobenzene (C6H5-NO2) is being reduced to aniline (C6H5-NH2) with the addition of hydrogen.

### Step 2: Identify the Reducing Agent
In the context of this reaction, we need to identify the reducing agent that provides the necessary hydrogen atoms. The reducing agent is a substance that donates electrons or hydrogen to another substance, thereby reducing it.

### Step 3: Recognize the Role of Sn/HCl
In this reaction, the reducing agent used is a combination of tin (Sn) and hydrochloric acid (HCl). Tin acts as a source of nascent hydrogen when it reacts with HCl.

### Step 4: Write the Reaction with the Reducing Agent
The complete reaction can be represented as:
\[ C_6H_5-NO_2 + 6[H] \text{ (from Sn/HCl)} \rightarrow C_6H_5-NH_2 + 2H_2O \]
Here, Sn provides the nascent hydrogen required for the reduction.

### Step 5: Conclusion
Thus, the reducing agent used in the reduction of nitrobenzene to aniline in acid medium is:
**Sn/HCl**

### Final Answer
The reducing agent used in this reaction is **Sn/HCl**.

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