Which of the following Beayer's reagent.

Options

A. Alkaline permanganate solution
B. Acidicied permanganate solution
C. Neutral permanganate solution
D. Aqueous bromine solution

Answer

To determine which of the following is Baeyer's reagent, we need to identify the correct chemical composition and characteristics of Baeyer's reagent.

### Step-by-Step Solution:

1. **Understanding Baeyer's Reagent**:
- Baeyer's reagent is known as alkaline permanganate solution. It is a solution of potassium permanganate (KMnO4) in a basic medium (usually sodium hydroxide, NaOH).

2. **Identifying the Characteristics**:
- The solution of Baeyer's reagent has a distinctive violet color due to the presence of permanganate ions (MnO4^-).

3. **Reactivity with Unsaturated Compounds**:
- When Baeyer's reagent is added to an organic compound containing double bonds (alkenes or alkynes), it reacts with these unsaturated bonds.
- This reaction leads to the oxidation of the double bonds and results in the formation of diols (vicinal diols), while the violet color of the solution disappears, turning colorless.

4. **Conclusion**:
- Therefore, the correct answer to the question "Which of the following is Baeyer's reagent?" is **alkaline permanganate solution (KMnO4 in NaOH)**.