Which of following reaction do not form `H_(2)`?

Options

A. `Fe+H_(2)SO_(4)`
B. `Sn+H_(2)SO_(4)`
C. `Cu+H_(2)SO_(4)`
D. `Zn+H_(2)SO_(4)`

Answer

To determine which of the following reactions do not form hydrogen gas (H₂), we will analyze each reaction step by step.

### Step 1: Analyze the first reaction
**Reaction:** Fe + H₂SO₄ → FeSO₄ + H₂

- **Explanation:** When iron (Fe) reacts with sulfuric acid (H₂SO₄), it forms iron(II) sulfate (FeSO₄) and releases hydrogen gas (H₂). Therefore, this reaction does produce H₂.

### Step 2: Analyze the second reaction
**Reaction:** Sn + H₂SO₄ → SnSO₄ + H₂

- **Explanation:** When tin (Sn) reacts with sulfuric acid (H₂SO₄), it forms tin(II) sulfate (SnSO₄) and releases hydrogen gas (H₂). Thus, this reaction also produces H₂.

### Step 3: Analyze the third reaction
**Reaction:** Cu + H₂SO₄ → CuSO₄ + SO₂ + H₂

- **Explanation:** When copper (Cu) reacts with sulfuric acid (H₂SO₄), it forms copper(II) sulfate (CuSO₄), sulfur dioxide (SO₂), and does not produce hydrogen gas (H₂). This is because copper is below hydrogen in the electrochemical series, meaning it cannot reduce H⁺ ions to form H₂. Therefore, this reaction does not produce H₂.

### Conclusion
Among the reactions analyzed:
- The first reaction (Fe + H₂SO₄) produces H₂.
- The second reaction (Sn + H₂SO₄) produces H₂.
- The third reaction (Cu + H₂SO₄) does not produce H₂.

Thus, the correct answer is **C: Cu + H₂SO₄**, as this reaction does not form hydrogen gas.

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