Which of the following acids has a peroxy linkage?

Options

A. sulhourors acid
B. pyrosulphuric acid
C. dithionic acid
D. Caro's acid

Explanation

To determine which of the given acids has a peroxy linkage, we will analyze the structures of each acid mentioned in the question.

### Step-by-Step Solution:

1. **Understanding Peroxy Linkage**:
- A peroxy linkage is characterized by the presence of an O-O bond (single bond between two oxygen atoms). This is crucial for identifying the correct acid.

2. **Analyzing the Acids**:
- **Sulphurous Acid (H₂SO₃)**:
- The structure of sulphurous acid has sulfur bonded to three oxygen atoms (one with a double bond and two with single bonds). There is no O-O bond present, so it does not have a peroxy linkage.

- **Pyrosulphuric Acid (H₂S₂O₇)**:
- The structure of pyrosulphuric acid consists of two sulfur atoms and seven oxygen atoms. The arrangement does not include an O-O bond, so it does not have a peroxy linkage.

- **Dithionic Acid (H₂S₂O₆)**:
- Dithionic acid has a structure with two sulfur atoms and six oxygen atoms. Similar to the previous acids, there is no O-O bond present, indicating no peroxy linkage.

- **Kerosene Acid (Peroxy Monosulfuric Acid, H₂SO₅)**:
- The structure of kerosene acid includes sulfur bonded to five oxygen atoms. In this structure, there is one O-O bond (peroxy linkage) present, confirming that this acid has a peroxy linkage.

3. **Conclusion**:
- Among the given options, **Kerosene Acid (Peroxy Monosulfuric Acid, H₂SO₅)** is the only acid that contains a peroxy linkage.

### Final Answer:
Kerosene Acid (Peroxy Monosulfuric Acid, H₂SO₅) has a peroxy linkage.

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