On oxidation with `KMnO_(4)` in acidic medium , `SO_(2)` is oxidised to

Options

A. `SO_(2)`
B. `H_(2)SO_(4)`
C. `SO_(3)^(2-)`
D. `H_(2)S`

Answer

To determine what sulfur dioxide (SO₂) is oxidized to when it reacts with potassium permanganate (KMnO₄) in an acidic medium, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Reactants and Conditions**:
- The reactants are sulfur dioxide (SO₂) and potassium permanganate (KMnO₄).
- The reaction occurs in an acidic medium.

2. **Understand the Role of KMnO₄**:
- KMnO₄ acts as a strong oxidizing agent in acidic conditions.
- It will facilitate the oxidation of SO₂.

3. **Determine the Oxidation States**:
- In SO₂, the oxidation state of sulfur (S) is +4.
- In KMnO₄, the oxidation state of manganese (Mn) is +7.

4. **Identify the Products of the Reaction**:
- When SO₂ is oxidized in the presence of KMnO₄, it forms sulfuric acid (H₂SO₄).
- The oxidation state of sulfur in H₂SO₄ is +6.

5. **Write the Balanced Chemical Equation**:
- The balanced equation for the reaction is:
\[ 2 KMnO₄ + 5 SO₂ + 2 H₂O \rightarrow 2 MnSO₄ + 2 H₂SO₄ \]
- This equation shows that KMnO₄ reduces while SO₂ gets oxidized.

6. **Analyze the Changes in Oxidation States**:
- For sulfur: +4 (in SO₂) changes to +6 (in H₂SO₄), indicating oxidation (loss of electrons).
- For manganese: +7 (in KMnO₄) changes to +2 (in MnSO₄), indicating reduction (gain of electrons).

7. **Conclusion**:
- Therefore, when sulfur dioxide (SO₂) is oxidized by KMnO₄ in acidic medium, it is oxidized to sulfuric acid (H₂SO₄).

### Final Answer:
SO₂ is oxidized to H₂SO₄ when reacted with KMnO₄ in acidic medium.

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