The electronegativity of phosphorus is maximum in

Options

A. `PCl_(5)`
B. `PClF_(4)`
C. `PCl_(2)F_(3)`
D. `PCl_(3)F_(2)`

Explanation

To determine in which compound phosphorus exhibits maximum electronegativity, we need to analyze the given compounds based on their structure and the electronegativity of the atoms bonded to phosphorus.

### Step-by-Step Solution:

1. **Identify the Compounds**: The compounds given are:
- A) PCl5
- B) PClF4
- C) PCl2F3
- D) PCl3F2

2. **Understand Electronegativity**: Electronegativity is the tendency of an atom to attract electrons in a bond. Fluorine (F) is more electronegative than chlorine (Cl). Therefore, when phosphorus (P) is bonded to fluorine, it will exhibit a more positive character compared to when it is bonded to chlorine.

3. **Analyze Each Compound**:
- **A) PCl5**: Phosphorus is bonded to 5 chlorine atoms. Since chlorine is less electronegative than fluorine, phosphorus will have a relatively higher positive character here, but it is surrounded by more electronegative atoms.
- **B) PClF4**: Phosphorus is bonded to 1 chlorine and 4 fluorine atoms. The presence of 4 highly electronegative fluorine atoms will increase the positive character of phosphorus, suggesting higher electronegativity.
- **C) PCl2F3**: Phosphorus is bonded to 2 chlorine and 3 fluorine atoms. The electronegativity effect is still present, but not as strong as in option B.
- **D) PCl3F2**: Phosphorus is bonded to 3 chlorine and 2 fluorine atoms. This configuration has fewer fluorine atoms compared to option B.

4. **Determine Maximum Electronegativity**: The more electronegative atoms (fluorine) bonded to phosphorus, the higher the positive charge on phosphorus, which indicates higher electronegativity. Therefore, the compound with the most fluorine atoms will show the maximum electronegativity for phosphorus.

5. **Conclusion**: Among the options, compound B (PClF4) has the maximum number of fluorine atoms (4), which means phosphorus will exhibit maximum electronegativity in this compound.

### Final Answer:
The electronegativity of phosphorus is maximum in **B) PClF4**.