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 about diborane (B2H6), let's analyze the properties and structure of diborane step by step.

### Step 1: Understanding the Structure of Diborane
Diborane (B2H6) consists of two boron atoms and six hydrogen atoms. The structure of diborane is unique because it contains both terminal and bridging hydrogen atoms.

### Step 2: Identifying the Types of Bonds
In diborane, there are:
- Four terminal B-H bonds (each connecting a boron atom to a hydrogen atom).
- Two bridging B-H bonds (which connect the two boron atoms through hydrogen atoms).

### Step 3: Geometrical Arrangement
The four terminal B-H bonds lie in the same plane, while the two bridging B-H bonds are positioned above and below this plane. This results in a three-dimensional structure that is not planar.

### Step 4: Analyzing the Statements
Now, let's analyze the statements provided:
1. All B-H bonds are on the same plane. (Incorrect)
2. Four terminal B-H bonds are in the plane and two are above and below the plane. (Correct)
3. It is a 12-electron species. (Correct)
4. Two BH3 units are connected by three-centered electron pair bonds. (Correct)

### Conclusion
The incorrect statement is: **"All B-H bonds are on the same plane."** This is false because while the terminal B-H bonds are in the same plane, the bridging B-H bonds are not.

### Final Answer
The incorrect statement is: **"All B-H bonds are on the same plane."**

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