Which one of the following represents the INCORRECT decreasing order of bond angles ?

Options

A. `CO_(2) gt BF_(3) gt CH_(4) gt H_(2)O`
B. `NO_(2)^(+) gt NO_(2) gt NO_(2)^(-)`
C. `BCl_(3) gt PCl_(3) gt AsCl_(3) gt BiCl_(3)`
D. `IO_(3)^(-) gt BrO_(3)^(-) gt ClO_(3)^(-)`

Explanation

To determine the INCORRECT decreasing order of bond angles from the options provided, we need to analyze the bond angles associated with different molecular geometries and the influence of lone pairs and hybridization on these angles. Here’s a step-by-step breakdown of the solution:

### Step 1: Identify the molecular geometries and bond angles
1. **Carbon Dioxide (CO2)**:
- Geometry: Linear
- Bond Angle: 180°

2. **Boron Trifluoride (BF3)**:
- Geometry: Trigonal Planar
- Bond Angle: 120°

3. **Methane (CH4)**:
- Geometry: Tetrahedral
- Bond Angle: 109.5°

4. **Water (H2O)**:
- Geometry: Bent (Angular)
- Bond Angle: 104.5°

### Step 2: Compare the bond angles
- The order of bond angles from highest to lowest is:
- CO2 (180°) > BF3 (120°) > CH4 (109.5°) > H2O (104.5°)

### Step 3: Analyze the next set of molecules
1. **Nitronium Ion (NO2+)**:
- Geometry: Linear
- Bond Angle: 180°

2. **Nitrogen Dioxide (NO2)**:
- Geometry: Bent
- Bond Angle: <120° (due to lone pair repulsion)

3. **Nitrite Ion (NO2−)**:
- Geometry: Bent
- Bond Angle: <120° (more lone pair repulsion than NO2)

### Step 4: Compare the bond angles for NO2, NO2+, and NO2−
- The order of bond angles is:
- NO2+ (180°) > NO2 (> NO2−)

### Step 5: Analyze the third set of molecules
1. **Boron Trichloride (BCl3)**:
- Geometry: Trigonal Planar
- Bond Angle: 120°

2. **Phosphorus, Arsenic, and Bismuth Compounds**:
- As we go down the group, the bond angles decrease due to increasing size and decreasing electronegativity.

### Step 6: Analyze the bond angles for halate ions
1. **Chlorate Ion (ClO3−)**:
- Geometry: Trigonal Pyramidal
- Bond Angle: >104.5° (due to lone pair)

2. **Bromate Ion (BrO3−)**:
- Geometry: Trigonal Pyramidal
- Bond Angle: <104.5°

3. **Iodate Ion (IO3−)**:
- Geometry: Trigonal Pyramidal
- Bond Angle: <104.5°

### Step 7: Compare the bond angles for ClO3−, BrO3−, and IO3−
- The order of bond angles should be:
- ClO3− > BrO3− > IO3− (due to decreasing electronegativity)

### Conclusion
After analyzing the bond angles and their corresponding molecular geometries, we find that the incorrect decreasing order of bond angles is the one that states:
- IO3− > BrO3− > ClO3− (this is incorrect).

### Final Answer
The incorrect option is the one that states the bond angles in the order of IO3− > BrO3− > ClO3−.