Question

The electron deficient compound that has 3c - 2e bond among the following:

• A. $B_2{H}_6$
• B. $A{l}_{2}C{l}_6$
• C. $BeC{l}_2$ polymer
• D. All of the above

Answer 1

The correct option is A $B_2{H}_6$



In $B_2{H}_6$, total number valence atomic orbitals = 14
(4 from each boron atom and one from each hydrogen atom)
Total number of valence electrons = 12
So in order to utilise all the valence orbitals, $B_2{H}_6$ possess 3c-2e bonds.
In $A{l}_{2}C{l}_6$ and $BeC{l}_2$ lone pairs are involved in bridge formation. Hence bridge bonds are 3c-4e bonds.