The H-B-H bridged angle in diborane is

Options

A. `121.5^@`
B. `97^@`
C. `119^@`
D. `133^@`

Answer

To determine the H-B-H bridged angle in diborane (B2H6), we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Structure of Diborane**:
- Diborane (B2H6) consists of two boron atoms and six hydrogen atoms.
- In its structure, there are four terminal hydrogen atoms and two bridge hydrogen atoms.

2. **Identifying the Types of Hydrogen Atoms**:
- The terminal hydrogens are directly bonded to the boron atoms.
- The bridge hydrogens are located between the two boron atoms, forming a bridge.

3. **Analyzing the Bond Angles**:
- The bond angle between the terminal hydrogen atoms (H-B-H) is approximately 120 degrees.
- The bond angle between the bridge hydrogen atoms (H-B-H) is what we need to find.

4. **Finding the Bridged Angle**:
- The bridged angle (H-B-H) in diborane is known to be approximately 97 degrees.
- This angle is formed due to the unique bonding arrangement in diborane, where the bridge hydrogens create a three-center two-electron bond.

5. **Conclusion**:
- Therefore, the H-B-H bridged angle in diborane is 97 degrees.

### Final Answer:
The H-B-H bridged angle in diborane is **97 degrees**.

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