The change in bond angle as the s - character of hybridized orbital decreases is ,

Options

A. Decreases
B. Increases
C. Does not change
D. Become zero

Answer

To solve the question regarding the change in bond angle as the s-character of hybridized orbitals decreases, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Hybridization**:
- Hybridization involves the mixing of atomic orbitals to form new hybrid orbitals, which can be used to form bonds. The type of hybridization depends on the steric number, which is determined by the number of bonded atoms and lone pairs around the central atom.

2. **Identifying Examples**:
- Let's consider three molecules: Methane (CH₄), Boron Trifluoride (BF₃), and Carbon Dioxide (CO₂).
- Methane has a steric number of 4 (4 bonds, no lone pairs) leading to sp³ hybridization.
- Boron Trifluoride has a steric number of 3 (3 bonds, no lone pairs) leading to sp² hybridization.
- Carbon Dioxide has a steric number of 2 (2 double bonds, no lone pairs) leading to sp hybridization.

3. **Calculating s-Character**:
- The s-character in hybridization can be calculated as follows:
- sp³: 25% s-character (1 s orbital out of 4 total orbitals)
- sp²: 33.3% s-character (1 s orbital out of 3 total orbitals)
- sp: 50% s-character (1 s orbital out of 2 total orbitals)

4. **Bond Angles**:
- The bond angles for these molecules are:
- CH₄ (sp³): 109.5°
- BF₃ (sp²): 120°
- CO₂ (sp): 180°
- As we can see, as the s-character increases, the bond angle also increases.

5. **Analyzing the Trend**:
- From the examples, we observe that:
- As the s-character decreases (from sp to sp² to sp³), the bond angle decreases.
- This indicates a direct relationship: **decreasing s-character leads to a decrease in bond angle**.

6. **Conclusion**:
- Therefore, if the s-character of hybridized orbitals decreases, the bond angle also decreases.

### Final Answer:
The change in bond angle as the s-character of hybridized orbital decreases is that the bond angle decreases.