When a salt is heated with dil `H_(2)SO_(4)` and `KMnO_(4)` solution the pink colour of `KMnO_(4)` is dicharged, the mixture may contain

Options

A. Sulphite
B. Carbonate
C. Nitrate
D. Bicarbonate

Answer

To solve the question regarding the mixture that may contain when a salt is heated with dilute H₂SO₄ and KMnO₄ solution, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants**:
- The reactants in this scenario are dilute sulfuric acid (H₂SO₄) and potassium permanganate (KMnO₄).

2. **Understand the Behavior of KMnO₄**:
- KMnO₄ is a strong oxidizing agent. When it is added to a solution, it imparts a pink color due to the presence of the MnO₄⁻ ion.

3. **Observe the Reaction**:
- The question states that the pink color of KMnO₄ is discharged upon heating the salt with the reagents. This indicates that KMnO₄ is being reduced, which means it is reacting with an anion present in the salt.

4. **Determine Possible Anions**:
- The possible anions provided in the question are:
- Sulphite (SO₃²⁻)
- Carbonate (CO₃²⁻)
- Nitrate (NO₃⁻)
- Bicarbonate (HCO₃⁻)

5. **Analyze Each Anion**:
- **Sulphite (SO₃²⁻)**: This can be oxidized to sulfate (SO₄²⁻) by KMnO₄.
- **Carbonate (CO₃²⁻)**: This does not get oxidized by KMnO₄.
- **Nitrate (NO₃⁻)**: This is already in a high oxidation state and does not get oxidized further.
- **Bicarbonate (HCO₃⁻)**: This cannot be oxidized to a higher oxidation state.

6. **Conclusion**:
- The only anion that can be oxidized by KMnO₄ is sulphite (SO₃²⁻). Therefore, the mixture must contain sulphite ions.

7. **Final Answer**:
- The correct answer is that the mixture may contain **sulphite (SO₃²⁻)**.