Reducing property of `SO_(2)` is shown in
A) `2H_(2)S+SO_(2)rarr 3S+2H_(2)O`
B) `I_(2)+SO_(2)+2H_(2)Orarr SO_(4)^(-2)+2I^(-)+4H^(+)`
C) `3Fe+SO_(2)rarr 2Fe+FeS`

Options

A. A
B. B
C. A, B
D. A, C

Answer

To determine the reducing property of sulfur dioxide (SO₂) in the given reactions, we need to analyze the oxidation states of sulfur and the other elements involved in each reaction. The reducing agent is the one that gets oxidized while causing the reduction of another substance.

### Step-by-Step Solution:

**Step 1: Analyze Reaction A**
- Reaction: \( 2H_2S + SO_2 \rightarrow 3S + 2H_2O \)
- Oxidation states:
- In \( H_2S \), sulfur (S) has an oxidation state of -2.
- In \( SO_2 \), sulfur has an oxidation state of +4.
- In elemental sulfur (S), the oxidation state is 0.
- Changes:
- \( S \) changes from -2 (in \( H_2S \)) to 0 (elemental S) - oxidation.
- \( S \) changes from +4 (in \( SO_2 \)) to 0 (elemental S) - reduction.
- Conclusion: Since sulfur in \( SO_2 \) is being reduced and \( H_2S \) is being oxidized, \( SO_2 \) is not acting as a reducing agent.

**Step 2: Analyze Reaction B**
- Reaction: \( I_2 + SO_2 + 2H_2O \rightarrow SO_4^{2-} + 2I^{-} + 4H^{+} \)
- Oxidation states:
- In \( SO_2 \), sulfur has an oxidation state of +4.
- In \( SO_4^{2-} \), sulfur has an oxidation state of +6.
- In \( I_2 \), iodine (I) has an oxidation state of 0.
- In \( I^{-} \), iodine has an oxidation state of -1.
- Changes:
- \( S \) changes from +4 (in \( SO_2 \)) to +6 (in \( SO_4^{2-} \)) - oxidation.
- \( I \) changes from 0 (in \( I_2 \)) to -1 (in \( I^{-} \)) - reduction.
- Conclusion: \( SO_2 \) is oxidized while \( I_2 \) is reduced, indicating that \( SO_2 \) acts as a reducing agent.

**Step 3: Analyze Reaction C**
- Reaction: \( 3Fe + SO_2 \rightarrow 2Fe + FeS \)
- Oxidation states:
- In elemental iron (Fe), the oxidation state is 0.
- In \( FeS \), iron has an oxidation state of +2 and sulfur has -2.
- Changes:
- Iron does not change its oxidation state (0 to 0).
- Sulfur changes from +4 (in \( SO_2 \)) to -2 (in \( FeS \)) - reduction.
- Conclusion: Since iron does not change its oxidation state, \( SO_2 \) is not acting as a reducing agent here.

### Final Conclusion:
The reaction that shows the reducing property of \( SO_2 \) is **B**: \( I_2 + SO_2 + 2H_2O \rightarrow SO_4^{2-} + 2I^{-} + 4H^{+} \).