`H_(2)O_(2)` exists in alkaline medium as

Options

A. `HO_(2)^(-)`
B. `H^(+)`
C. `H_(3)O_(2)^(+)`
D. `O^(2-)`

Answer

To determine the form in which hydrogen peroxide (H₂O₂) exists in an alkaline medium, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Alkaline Medium**:
- An alkaline medium is characterized by a high concentration of hydroxide ions (OH⁻). This means that the pH of the solution is greater than 7.

2. **Behavior of H₂O₂ in Alkaline Medium**:
- In an alkaline medium, H₂O₂ can behave as a base. This is because the presence of hydroxide ions allows H₂O₂ to donate protons (H⁺ ions).

3. **Reaction of H₂O₂ with Hydroxide Ions**:
- When H₂O₂ is in an alkaline medium, it can react with hydroxide ions (OH⁻). The hydroxide ions can extract a proton (H⁺) from H₂O₂, leading to the formation of water (H₂O) and a negatively charged peroxide ion (O₂²⁻).

4. **Formation of Peroxide Ion**:
- The reaction can be represented as:
\[ H₂O₂ + OH⁻ \rightarrow O₂^{2-} + H₂O \]
- Here, the H₂O₂ molecule loses a hydrogen ion (H⁺) and forms a peroxide ion (O₂²⁻) along with water.

5. **Conclusion**:
- Therefore, in an alkaline medium, H₂O₂ exists primarily as the peroxide ion (O₂²⁻).

### Final Answer:
H₂O₂ exists in alkaline medium as the peroxide ion (O₂²⁻).

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