Hinsberg's reagent is:

Options

A. `C_6H_5COCl`
B. `CH_3COCl`
C. `C_6H_5CH_2Cl`
D. `C_6H_5SO_2Cl`

Explanation

To answer the question "Hinsberg's reagent is:", we will follow these steps:

### Step 1: Identify Hinsberg's Reagent
Hinsberg's reagent is known to be benzene sulfonyl chloride.

### Step 2: Understand the Structure
Benzene sulfonyl chloride has a specific structure which includes a benzene ring attached to a sulfonyl group (SO2) and a chlorine atom. The chemical formula can be represented as C6H5SO2Cl.

### Step 3: Distinguishing Amines
Hinsberg's reagent is primarily used to differentiate between primary, secondary, and tertiary amines. It reacts with these amines to form sulfonamides, which can be further analyzed to determine the type of amine.

### Step 4: Analyze the Options
When presented with multiple-choice options, we need to identify which one corresponds to benzene sulfonyl chloride.

### Step 5: Conclusion
After analyzing the options, the correct answer is the one that represents benzene sulfonyl chloride, which is option D.

### Final Answer
Hinsberg's reagent is benzene sulfonyl chloride (C6H5SO2Cl).

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