Lucas reagent is:

Options

A. Anhydrous `ZnCl_(2)+HCl(conc.)`
B. `MnO_(2)+H_(2)O`
C. `H_(2)SO_(4)+HCl`
D. `NO+H_(2)O`

Explanation

**Step-by-Step Solution:**

1. **Understanding Lucas Reagent**: Lucas reagent is a chemical reagent used primarily in organic chemistry to differentiate between primary, secondary, and tertiary alcohols.

2. **Components of Lucas Reagent**: The Lucas reagent is composed of anhydrous zinc chloride (ZnCl2) and concentrated hydrochloric acid (HCl).

3. **Purpose of Lucas Reagent**: The main purpose of Lucas reagent is to distinguish between different types of alcohols. When alcohols react with Lucas reagent, the reaction rate varies based on the type of alcohol:
- Tertiary alcohols react quickly, leading to the formation of an alkyl chloride.
- Secondary alcohols react more slowly.
- Primary alcohols do not react at room temperature.

4. **Identifying the Correct Option**: Based on the components and purpose of Lucas reagent, the correct answer is that Lucas reagent is a mixture of anhydrous ZnCl2 and concentrated HCl.

5. **Conclusion**: Therefore, the correct option is the first one, which states that Lucas reagent is anhydrous ZnCl2 along with concentrated HCl.

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