Question

Assertion: In diborane, each B atom is $s{p}^3$ hybridised.

Reason: In diborane, the terminal 2-centre-2-electron B-H bonds are called banana bonds.

Select the correct option.

• A. Both A and R are true and R is the correct explanation of A.
• B. Both A and R are true but R is not the correct explanation of A.
• C. A is true but R is false.
• D. A is false but R is true.

Answer 1

The correct option is C A is true but R is false.

The four-terminal hydrogen atoms and the two boron atoms are lying in one plane. Above and below this plane, two bridging hydrogen atoms are there.

The four-terminal B-H bonds are in regular two centre-two electron bonds.

Two B–H–B bridging bonds are formed, each of which consists of two electrons, forming what are called three- center-two-electron bonds (i.e., 3 atoms share 2 electrons) – sometimes called 'banana' bonds.

Each B atom uses sp3 hybrids for the bonding.

Assertion is true but reason is false.

Option C is correct.