The acid containing `S - O - O - S` bond is 

Options

A. `H_(2)SO_(5)`
B. `H_(2)S_(2)O_(7)`
C. `H_(2)S_(2)O_(6)`
D. `H_(2)S_(2)O_(8)`

Answer

To determine the acid containing the `S - O - O - S` bond, we will analyze the given options step by step.

### Step 1: Identify the options
The options provided are:
1. H₂SO₅
2. H₂S₂O₇
3. H₂S₄O₆
4. H₂S₂O₈

### Step 2: Analyze the structure of each acid
1. **H₂SO₅ (Peroxymonosulfuric acid)**:
- The structure of H₂SO₅ does not contain the `S - O - O - S` bond. It has a different arrangement of sulfur and oxygen.

2. **H₂S₂O₇ (Disulfuric acid)**:
- The structure of H₂S₂O₇ also does not contain the `S - O - O - S` bond. It is composed of two sulfur atoms but arranged differently.

3. **H₂S₄O₆**:
- The structure of H₂S₄O₆ does not contain the `S - O - O - S` bond either. This compound has a different configuration.

4. **H₂S₂O₈ (Peroxydisulfuric acid)**:
- The structure of H₂S₂O₈ shows the presence of the `S - O - O - S` bond. This is the correct structure that matches the requirement of the question.

### Conclusion
The acid containing the `S - O - O - S` bond is **H₂S₂O₈**.

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