B−H−B bridge in B2H6 is formed by the involvement of:
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 3C−2e− bonds.