Question

In hydride (P) (select correct statement)

• A. the central atom has trigonal planar geometry.
• B. all H-atom lie in the same plane.
• C. all four terminal B-H bond lengths are equivalent but that of four bridging B-H bond lengths are not equivalent.
• D. a three-centre two-electron bond (3c-2e) is formed by overlap of an $s{p}^3$ hybrid orbital from each boron atom with the 1s orbital of hydrogen atom.

Answer 1

The correct option is D a three-centre two-electron bond (3c-2e) is formed by overlap of an $s{p}^3$ hybrid orbital from each boron atom with the 1s orbital of hydrogen atom.

There is $2p\pi -2p\pi$ bonding.
$4B{F}_3\left(A\right)+3LiAl{H}_4\stackrel{Ether}{\to }2B_2{H}_6\left(P\right)+3LiAl{F}_4$
$B_2{H}_6+3O_2\to B_2{O}_3+3H_{2}O+Heat$.
Molecular weight of compound $\left(P\right)=21.76+6=27.76$.
$\%$ of H in compound (P) i.e., $B_2{H}_6=\frac{6}{27.76}\times 100=21.72$
$B_2{H}_6+2N{H}_3\stackrel{\Delta }{\to }{B}_3{N}_3{H}_6$ (inorganic benzene) $+H_2$.