Which of the following compounds consists of P-P linkage?

Options

A. Hypo phosphoric acid
B. Pyrophosphorous acid
C. Dipolyphosphoric acid
D. Metaphosphoric acid

Explanation

To determine which of the given compounds consists of a P-P linkage, we will analyze each compound step by step.

### Step 1: Analyze Hypophosphoric Acid
- **Structure**: Hypophosphoric acid has the formula H₄P₂O₆. Its structure can be represented as:
- P=O (double bond)
- P=O (double bond)
- OH groups attached to both phosphorus atoms.
- **Linkage**: In this structure, there is a direct bond between two phosphorus atoms (P-P), indicating the presence of a P-P linkage.

### Step 2: Analyze Pyrophosphorus Acid
- **Structure**: Pyrophosphorus acid has the formula H₄P₂O₅. Its structure can be represented as:
- P-O-P (single bond)
- Each phosphorus atom has one double bond with oxygen (P=O).
- **Linkage**: This structure also shows a direct bond between two phosphorus atoms (P-P), indicating the presence of a P-P linkage.

### Step 3: Analyze Diphosphoric Acid
- **Structure**: Diphosphoric acid (also known as orthophosphoric acid) has the formula H₄P₂O₇. Its structure can be represented as:
- P=O (double bond)
- O (bridging oxygen)
- P=O (double bond)
- OH groups attached to both phosphorus atoms.
- **Linkage**: This structure shows a direct bond between two phosphorus atoms (P-P) through the bridging oxygen, indicating the presence of a P-P linkage.

### Step 4: Analyze Metaphosphoric Acid
- **Structure**: Metaphosphoric acid has the formula HPO₃. Its structure can be represented as:
- P=O (double bond)
- P=O (double bond)
- OH group attached to phosphorus.
- **Linkage**: In this case, there is no direct bond between two phosphorus atoms; hence, there is no P-P linkage.

### Conclusion
After analyzing all the compounds:
- **Hypophosphoric Acid** (Option A), **Pyrophosphorus Acid** (Option B), and **Diphosphoric Acid** (Option C) all contain P-P linkages.
- **Metaphosphoric Acid** (Option D) does not contain a P-P linkage.

### Final Answer
The compounds that consist of P-P linkage are:
- **Option A: Hypophosphoric Acid**
- **Option B: Pyrophosphorus Acid**
- **Option C: Diphosphoric Acid**