Which has maximum bond angle?

Options

A. `NH_(3)`
B. `PH_(3)`
C. `AsH_(3)`
D. `SbH_(3)`

Answer

To determine which molecule has the maximum bond angle among NH3, PH3, SH3, and SbH3, we will analyze the bond angles based on the trends in the periodic table and the molecular geometry of each compound.

### Step-by-Step Solution:

1. **Understanding the Compounds**:
- NH3 (Ammonia)
- PH3 (Phosphine)
- SH3 (Hydrogen sulfide)
- SbH3 (Stibine)

2. **Periodic Trends**:
- As we move down a group in the periodic table, the atomic radius increases and electronegativity decreases. This affects the bond angles in the compounds formed by these elements.

3. **Bond Angles of Each Compound**:
- **NH3**: The bond angle is approximately 107 degrees. This is due to the presence of a lone pair on nitrogen, which pushes the hydrogen atoms closer together.
- **PH3**: The bond angle is approximately 93 degrees. The larger size of phosphorus compared to nitrogen results in a more significant bond angle reduction.
- **SH3**: The bond angle is approximately 92 degrees. Similar to PH3, the larger size of sulfur leads to a decrease in the bond angle.
- **SbH3**: The bond angle is approximately 91 degrees. The trend continues with antimony, which is even larger than phosphorus and sulfur.

4. **Comparing the Bond Angles**:
- From the bond angles calculated:
- NH3: 107 degrees
- PH3: 93 degrees
- SH3: 92 degrees
- SbH3: 91 degrees
- It is clear that NH3 has the largest bond angle.

5. **Conclusion**:
- Therefore, the molecule with the maximum bond angle is **NH3**.

### Final Answer:
The molecule with the maximum bond angle is **NH3**.