Collin's reagent is

Options

A. `MNO_(2)//HCl`
B. `MNO_(4)//C_(2)H_(5)N`
C. `K_(2)Cr_(2)O_(7)//H_(2)SO_(4)`
D. `Cr_(2)O_(3)//2C_(5)H_(5)N`

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about "Collin's reagent." We need to identify what it is and its components.

2. **Identifying Collin's Reagent**: Collin's reagent is a specific reagent used in organic chemistry, particularly for the oxidation of alcohols to aldehydes and ketones. It is made from chromium compounds.

3. **Components of Collin's Reagent**: The main components of Collin's reagent are chromium trioxide (CrO3) and pyridine (C5H5N). It is typically used in a solvent like dichloromethane (CH2Cl2).

4. **Chemical Reaction**: When Collin's reagent is used, the chromium trioxide oxidizes the alcohol, while pyridine acts as a base to facilitate the reaction.

5. **Conclusion**: Therefore, Collin's reagent can be summarized as a mixture of chromium trioxide and pyridine, often used in organic synthesis for oxidation reactions.

**Final Answer**: Collin's reagent is a mixture of chromium trioxide (CrO3) and pyridine (C5H5N), used for the oxidation of alcohols.

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