The statements regarding oxyacids of phosphorous are
i) `HPO_(3)` molecule is monobasic acid
ii) `H_(4)P_(2)O_(6)` molecule has `P - P` bond
iii) `H_(4)P_(2)O_(7)` molecule has `P - O - P` linkage
The correct combination is

Options

A. All are correct
B. Only ii is correct
C. ii & iii are correct
D. i & ii are correct

Answer

To determine the correct combination of statements regarding the oxyacids of phosphorus, we will analyze each statement one by one.

### Step 1: Analyze the first statement
**Statement i:** HPO₃ molecule is a monobasic acid.

- **Explanation:** HPO₃ is known as metaphosphoric acid. In this molecule, there is one hydroxyl group (-OH) associated with phosphorus. The basicity of an acid is determined by the number of hydrogen ions (H⁺) it can donate. Since HPO₃ has only one -OH group, it can donate only one H⁺ ion, making it a monobasic acid.

**Conclusion:** This statement is correct.

### Step 2: Analyze the second statement
**Statement ii:** H₄P₂O₆ molecule has a P-P bond.

- **Explanation:** H₄P₂O₆ is known as diphosphoric acid. In its structure, there is a direct bond between two phosphorus atoms (P-P bond). This can be visualized in the molecular structure where two phosphorus atoms are linked directly to each other.

**Conclusion:** This statement is correct.

### Step 3: Analyze the third statement
**Statement iii:** H₄P₂O₇ molecule has a P-O-P linkage.

- **Explanation:** H₄P₂O₇ is known as pyrophosphoric acid. In this molecule, there is a linkage between two phosphorus atoms through an oxygen atom (P-O-P linkage). This is characteristic of pyrophosphoric acid, where the two phosphorus atoms are connected via an oxygen atom.

**Conclusion:** This statement is correct.

### Final Conclusion
All three statements regarding the oxyacids of phosphorus are correct. Therefore, the correct combination is:

**Answer:** All statements are correct.

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