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's reaction, we need to understand the process and the components involved. Here’s a step-by-step breakdown:

### Step 1: Understand Diazonium Salts
- **Definition**: Diazonium salts are compounds containing the diazonium group (-N2^+), which is typically formed from primary aromatic amines (like aniline) when treated with sodium nitrite (NaNO2) and hydrochloric acid (HCl).
- **Formation**: For example, aniline reacts with NaNO2 and HCl to form benzene diazonium chloride.

### Step 2: Identify the Sandmeyer's Reaction
- **Reaction Overview**: The Sandmeyer reaction involves the substitution of the diazonium group (-N2^+) in diazonium salts with other groups, typically halides (like Cl, Br) or cyanide (CN).
- **General Reaction**:
- When benzene diazonium chloride is treated with copper(I) chloride (CuCl) in the presence of HCl, it forms chlorobenzene and nitrogen gas (N2).
- Similarly, using CuBr leads to bromobenzene, and CuCN leads to cyanobenzene.

### Step 3: Analyze the Substituents
- **Substituents in Sandmeyer's Reaction**: The -NH-X group (where X can be Cl, Br, or CN) is replaced by a halide group or cyanide group.
- **Halide Group**: The halides (Cl and Br) are classified as halogen groups, which are the primary replacements in the Sandmeyer reaction.

### Step 4: Evaluate the Options
- **Options**: The question implies that the -NH-X group is replaced by a specific group.
- **Halide Group**: Correct, as the diazonium salt is replaced by Cl or Br.
- **Nitro Group (NO2)**: Incorrect, as this is not a product of the Sandmeyer reaction.
- **Hydroxyl Group (OH)**: Incorrect, as this does not occur in the Sandmeyer reaction.
- **Amino Group (NH2)**: Incorrect, as this is not a product of the Sandmeyer reaction.

### Conclusion
- The correct answer is that the -NH-X group of diazonium salt is replaced by a **halide group**.

### Final Answer
- The -NH-X group of diazonium salt is replaced by a **halide group**.

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