Question

The correct statement(s) regarding diborane $\left(B_2{H}_6\right)$ is/are:

• A. Maximum six hydrogen atoms can lie in a plane
• B. Maximum six atoms can lie in a plane
• C. Bridging $B-H_b$ bond is longer than terminal $B-H_t$ bond
• D. Terminal $H_t-B-H_t$ bond angle is greater than bridging $H_b-B-H_b$ bond angle

Answer 1

Answer: (B), (C), (D)

The correct options are
B Maximum six atoms can lie in a plane
C Bridging $B-H_b$ bond is longer than terminal $B-H_t$ bond
D Terminal $H_t-B-H_t$ bond angle is greater than bridging $H_b-B-H_b$ bond angle

Maximum four hydrogen atoms can lie in a same plane with two Boron. So maximum six atoms can lie in a plane.

Bridging $(B-H_b)$ bond length greater than $B-H_t$ terminal bond. Bridging bonds are 3 centre - 2 electron bonds and hence they are longer.

$(H_t-B-H_t)$ bond angle is greater than bridging $(H_b-H-H_b)$ bond angle.