In the Sandmeyer's reaction, `-NH-X` group of diazonium salt is replaced by

Options

A. Halide group
B. Nitro group
C. `-OH` group
D. `NHNH_(2)` group

Answer

To solve the question regarding the Sandmeyer reaction and the replacement of the `-NH-X` group of diazonium salt, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Diazonium Salts**:
- Diazonium salts have the general formula Ar-N₂⁺X⁻, where Ar represents an aryl group (like benzene), N₂⁺ is the diazonium part, and X⁻ is a halide ion (like Cl⁻ or Br⁻).

2. **Identifying the Sandmeyer Reaction**:
- The Sandmeyer reaction is a chemical reaction that involves the substitution of the diazonium group (N₂) with a nucleophile. This is typically done using copper salts as catalysts.

3. **Common Nucleophiles in Sandmeyer Reaction**:
- The common nucleophiles that can replace the diazonium group in the Sandmeyer reaction include halides (Cl⁻, Br⁻) and cyanide (CN⁻).

4. **Reaction Mechanism**:
- In the presence of a copper(I) halide (like CuCl or CuBr), the diazonium salt reacts to replace the N₂ group with the halide ion. For example:
- Ar-N₂⁺Cl⁻ + CuCl → Ar-Cl + N₂↑
- Similarly, for cyanide:
- Ar-N₂⁺CN⁻ + CuCN → Ar-CN + N₂↑

5. **Conclusion**:
- Therefore, in the Sandmeyer reaction, the `-NH-X` group of diazonium salt is replaced by halide ions (like Cl⁻ or Br⁻) or cyanide (CN⁻).

### Final Answer:
In the Sandmeyer reaction, the `-NH-X` group of diazonium salt is replaced by halide ions (Cl⁻, Br⁻) or cyanide (CN⁻).

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