Question

In the structure of diborane, the number of 2-centre-2-electron bonds is X and 3-centre-2-electron bonds is Y. The value of (X + Y) is:

• A. 5
• B. 6
• C. 4
• D. 8

Hint:

Diborane is an electron-deficient compound with unusual 3-centre-2-electron bonds forming bridges between boron atoms.

Answer 1

The Correct Option is B

Diborane (B$_2$H$_6$) contains:
- Four terminal B-H bonds (2c-2e), so X = 4
- Two bridging hydrogen bonds (3c-2e), so Y = 2
Thus, X + Y = 4 + 2 = 6