Question

$B-H-B$ bridge in $B_2{H}_6$ is formed by the sign of :

• A. 2 electrons.
• B. 4 electrons.
• C. 1 electrons.
• D. 3 electrons.

Answer 1

The correct option is A 2 electrons.

The structure of diborane is shown in fig. The four terminal hydrogen atoms and the two boron atoms lie in one plane. Above and below this plane, there are two bridging hydrogen atoms. The four terminal B-H bonds are regular two centre-two electron bonds while the two bridge (B-H-B) bonds are different and can be described in terms of three centre - two electron bonds.