Baeyer's reagent is

Options

A. alkaline `KMnO_4`
B. acidified `KMnO_4`
C. neutral `KMnO_4`
D. aqueous bromine water

Explanation

**Step-by-Step Solution:**

1. **Understanding Baeyer's Reagent**: Baeyer's reagent is a chemical reagent used primarily for the detection of unsaturation (double bonds) in organic compounds. It is important to identify the specific composition of Baeyer's reagent.

2. **Identifying the Components**: The key component of Baeyer's reagent is potassium permanganate (KMnO4). In its use as Baeyer's reagent, it is prepared in an alkaline solution.

3. **Alkaline Solution**: The alkaline solution is typically made by dissolving potassium permanganate in water with a base, such as sodium hydroxide (NaOH). This results in a cold alkaline solution of potassium permanganate.

4. **Color of Baeyer's Reagent**: The solution of potassium permanganate in alkaline conditions is characterized by its violet color. This color is due to the presence of the permanganate ion (MnO4^-).

5. **Oxidizing Properties**: Baeyer's reagent is known for its strong oxidizing properties. It reacts with compounds that have double bonds (alkenes) and reduces the permanganate ion, causing the violet color to disappear.

6. **Conclusion**: Based on the above points, we conclude that Baeyer's reagent is an alkaline solution of potassium permanganate.

7. **Correct Answer**: Therefore, the correct answer to the question "Baeyer's reagent is" is **Alkaline Chaminophore** (which refers to the alkaline solution of potassium permanganate).

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