Correct order of bond angle for `O-P-X`
`P{:(O),(/),( "\" ),(X):}`
in the given molecules is
`underset(I)(POF_(3)) underset(II)(POCl_(3)) underset(III)(POBr_(3)) underset(IV)(POI_(3))` are

Options

A. `I gt II gt III gt IV `
B. `IV gt III gt II gt I`
C. `II gt III gt I gt IV `
D. `III gt II gt IV gt I`

Answer

To determine the correct order of bond angles for the molecules POF₃, POCl₃, POBr₃, and POI₃, we need to analyze the bond angles based on the size and charge density of the halogen atoms (F, Cl, Br, I) involved in these compounds.

### Step-by-Step Solution:

1. **Understanding Charge Density**:
- Charge density is defined as the ratio of charge to the size of the atom. For halogens, they all have 7 valence electrons, but their sizes increase down the group (F < Cl < Br < I).
- As the size of the atom increases, the charge density decreases.

2. **Analyzing the Halogens**:
- Fluorine (F) has the smallest size and thus the highest charge density.
- Chlorine (Cl) is larger than fluorine, so it has a lower charge density than F but higher than Br and I.
- Bromine (Br) is larger than Cl, resulting in an even lower charge density.
- Iodine (I) is the largest, hence it has the lowest charge density.

3. **Impact on Bond Angles**:
- The bond angle is influenced by the charge density of the halogen. Higher charge density leads to greater lone pair-lone pair repulsion, which increases the bond angle.
- Conversely, lower charge density results in less repulsion and thus smaller bond angles.

4. **Order of Bond Angles**:
- Since F has the highest charge density, the bond angle in POF₃ will be the largest.
- Next, POCl₃ will have a smaller bond angle than POF₃ but larger than POBr₃ due to Cl having a higher charge density than Br.
- POBr₃ will have a smaller bond angle than POCl₃, and finally, POI₃ will have the smallest bond angle due to I having the lowest charge density.

5. **Final Order**:
- Therefore, the correct order of bond angles is:
\[ \text{POF}_3 > \text{POCl}_3 > \text{POBr}_3 > \text{POI}_3 \]

### Conclusion:
The correct order of bond angles for the molecules POF₃, POCl₃, POBr₃, and POI₃ is:
\[ \text{POF}_3 > \text{POCl}_3 > \text{POBr}_3 > \text{POI}_3 \]