In which of the following molecules, the number of possible `angleXAX` angles is maximum in the anionic part of their solid state ? [A : Central atom , X : Surrounding atom ]

Options

A. `PBr_(5)`
B. `N_(2)O_(5)`
C. `PCl_(5)`
D. `Cl_(2)O_(6)`

Answer

To solve the question regarding the number of possible `angle XAX` angles in the anionic part of the given molecules, we will analyze each molecule step by step.

### Step 1: Identify the Dissociation of Each Molecule
1. **PBr5**:
- Dissociates into PBr4⁺ + Br⁻.
- The anionic part is Br⁻, which is a single atom and does not have any bond angles.

2. **N2O5**:
- Dissociates into NO2⁺ + NO3⁻.
- The anionic part is NO3⁻.
- NO3⁻ has a trigonal planar structure due to sp² hybridization, leading to bond angles of approximately 120 degrees.

3. **PCl5**:
- Dissociates into PCl4⁺ + Cl⁻.
- The anionic part is Cl⁻, which is also a single atom and does not have any bond angles.

4. **Cl2O6**:
- Dissociates into ClO2⁺ + ClO4⁻.
- The anionic part is ClO4⁻.
- ClO4⁻ has a tetrahedral structure due to sp³ hybridization, leading to bond angles of approximately 109.5 degrees.

### Step 2: Count the Possible `angle XAX` Angles
- **PBr5**: No angles (only Br⁻).
- **N2O5**: One angle (120 degrees in NO3⁻).
- **PCl5**: No angles (only Cl⁻).
- **Cl2O6**: One angle (approximately 109.5 degrees in ClO4⁻).

### Step 3: Compare the Angles
From the analysis:
- N2O5 (NO3⁻) has one angle (120 degrees).
- Cl2O6 (ClO4⁻) has one angle (approximately 109.5 degrees).
- PBr5 and PCl5 do not contribute any angles.

### Conclusion
The maximum number of possible `angle XAX` angles in the anionic part is found in **N2O5** (NO3⁻) with one angle of approximately 120 degrees.

### Final Answer
The answer is **N2O5**.

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