In Diborane , the incorrect statement is

Options

A. All 6 B-H bond are on same plane
B. 4 B- H bonds are on the plane and two B- H bonds above and below the plane
C. It is the 12 `e^(-)` species
D. Two `BH_(3)` are attached with three centre electron pair bond

Answer

To determine the incorrect statement regarding diborane (B2H6), we will analyze the properties and structure of the molecule step by step.

### Step-by-Step Solution:

1. **Identify the Molecular Formula**:
- Diborane is represented by the formula B2H6. This indicates that it contains two boron (B) atoms and six hydrogen (H) atoms.

2. **Understand the Structure**:
- Diborane has a non-planar structure. It consists of two boron atoms and six hydrogen atoms arranged in a specific way.

3. **Bonding in Diborane**:
- Each boron atom has three valence electrons. In diborane, boron forms bonds with hydrogen atoms and also shares electrons with the other boron atom.

4. **Types of Bonds**:
- Diborane contains two types of bonds: terminal B-H bonds and bridging B-H bonds. The terminal B-H bonds are connected to hydrogen atoms directly, while the bridging B-H bonds connect the two boron atoms.

5. **Bond Angles**:
- The bond angles in diborane are important. The bond angle for the terminal B-H bonds is approximately 122 degrees, while the bond angle for the bridging B-H bonds is about 97 degrees.

6. **Electron Count**:
- To determine if diborane is a stable molecule, we can count the total number of valence electrons. Each B contributes 3 electrons (2 B atoms = 6 electrons) and each H contributes 1 electron (6 H atoms = 6 electrons). Therefore, the total is 6 + 6 = 12 electrons, confirming that diborane is a 12-electron species.

7. **Analyzing Statements**:
- Now we need to analyze the statements provided regarding diborane:
- **Statement A**: All BH bonds are on the same plane. (This is incorrect)
- **Statement B**: Four BH bonds are in the plane and two BH bonds are above and below the plane. (This is correct)
- **Statement C**: It is a 12 electron species. (This is correct)
- **Statement D**: Two BH3 units are connected by three-center two-electron bonds. (This is correct)

8. **Conclusion**:
- The incorrect statement is **Statement A**: "All BH bonds are on the same plane." This is false because the structure of diborane is non-planar, with some bonds above and below the plane.

### Final Answer:
The incorrect statement is **A**: "All BH bonds are on the same plane."