`C_6 H_5 NH_2 underset(0^@ C) overset( NaNO_2 //HCI)to (A) overset(H_3 OO_2 // H_2 O ) to (B ) ` the compound (B ) is :

Options

A. `C_(6 ) H_(5 ) OH`
B. `C_6 H_5 CH_2 OH`
C. `C_6 H_6`
D. none of these

Answer

To solve the given problem step by step, we will analyze the reactions taking place with aniline (C₆H₅NH₂) and identify the final product (B).

### Step 1: Identify the starting compound
The starting compound is aniline, which has the molecular formula C₆H₅NH₂.

### Step 2: Perform diazotization
Aniline reacts with sodium nitrite (NaNO₂) in the presence of hydrochloric acid (HCl) at 0°C. This reaction is known as diazotization. The amino group (NH₂) of aniline is converted into a diazonium group (N₂⁺), resulting in the formation of benzenediazonium chloride (C₆H₅N₂Cl).

**Reaction:**
\[ \text{C}_6\text{H}_5\text{NH}_2 + \text{NaNO}_2 + \text{HCl} \rightarrow \text{C}_6\text{H}_5\text{N}_2\text{Cl} + \text{NaCl} + \text{H}_2\text{O} \]

### Step 3: Reduction of diazonium salt
Next, the benzenediazonium chloride (C₆H₅N₂Cl) is treated with phosphorous acid (H₃PO₂) in the presence of water. This reaction is a reduction process where the diazonium group is replaced by a hydrogen atom, resulting in the formation of benzene (C₆H₆).

**Reaction:**
\[ \text{C}_6\text{H}_5\text{N}_2\text{Cl} + \text{H}_3\text{PO}_2 \rightarrow \text{C}_6\text{H}_6 + \text{N}_2 + \text{HCl} + \text{H}_3\text{PO}_3 \]

### Step 4: Identify the final product (B)
The final product (B) after the reduction of benzenediazonium chloride is benzene (C₆H₆).

### Conclusion
Thus, the compound (B) is benzene (C₆H₆).

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