Hot concentrated sulphuric acid is a moderately strong oxidizing agent. Which of the following reaction does not show oxidizing behaviour?

Options

A. (a) `Cu + 2H_(2)SO_(4) rarr CuSO_4 + SO_(2) + 2H_(2)O`
B. (b) `3S + 2H_(2)SO_(4) rarr 3SO_(2) + 2H_(2)O`
C. (c) `C + 2H_(2)SO_(4) rarr CO_(2) + 2SO_(2) + 2H_(2)O`
D. (d) `CaF_(2) + H_(2)SO_(4) rarr CaSO_(4) + 2HF`

Explanation

To determine which reaction does not exhibit oxidizing behavior by hot concentrated sulfuric acid (H₂SO₄), we need to analyze each of the provided reactions and check the oxidation states of the elements involved.

### Step-by-Step Solution:

1. **Understanding Oxidizing Agents:**
- An oxidizing agent is a substance that can oxidize another substance by accepting electrons and itself gets reduced in the process.

2. **Analyzing Each Reaction:**

**Option A: Cu + 2H₂SO₄ → CuSO₄ + SO₂ + 2H₂O**
- Oxidation states:
- Cu (0) → Cu²⁺ (+2)
- S in H₂SO₄ (+6) → S in SO₂ (+4)
- Copper is oxidized (0 to +2) and sulfur is reduced (+6 to +4).
- This is a redox reaction, and H₂SO₄ acts as an oxidizing agent.

**Option B: 3S + 2H₂SO₄ → 3SO₂ + 2H₂O**
- Oxidation states:
- S (0) → S in SO₂ (+4)
- S in H₂SO₄ (+6) → S in SO₂ (+4)
- Sulfur is oxidized (0 to +4) and sulfur in H₂SO₄ is reduced (+6 to +4).
- This is also a redox reaction, and H₂SO₄ acts as an oxidizing agent.

**Option C: C + 2H₂SO₄ → CO₂ + 2SO₂ + 2H₂O**
- Oxidation states:
- C (0) → C in CO₂ (+4)
- S in H₂SO₄ (+6) → S in SO₂ (+4)
- Carbon is oxidized (0 to +4) and sulfur in H₂SO₄ is reduced (+6 to +4).
- This is a redox reaction, and H₂SO₄ acts as an oxidizing agent.

**Option D: CaF₂ + H₂SO₄ → CaSO₄ + 2HF**
- Oxidation states:
- Ca (+2) and F (-1) in CaF₂ remain unchanged.
- H in H₂SO₄ (+1) and S (+6) remain unchanged in CaSO₄.
- H in HF (+1) and F (-1) remain unchanged.
- No change in oxidation states indicates that there is no oxidation or reduction occurring.
- This is a double displacement reaction, not a redox reaction, and H₂SO₄ does not act as an oxidizing agent.

3. **Conclusion:**
- The reaction that does not show oxidizing behavior of H₂SO₄ is **Option D: CaF₂ + H₂SO₄ → CaSO₄ + 2HF**.