Question

In diborane the two H-B-H angles are nearly

• A. $60°,120°$
• B. $95°,120°$
• C. $95°,150°$
• D. $120°,180$

Answer 1

The correct option is B

$95°,120°$

Explanation for correct option:-

Option (B) $95°,120°$

• Chemical formula of Diborane is ${\mathrm{B}}_2{\mathrm{H}}_6$and its structure is:

• From the structure we can see that there are two hydrogen atoms on the left and two hydrogen atoms on the right.
• These two hydrogen atoms are known as terminal hydrogens, and also two Boron atoms lie in the same plane.
• The rest two hydrogen atoms form bridges, where one above and the other is below, lie in a plane that is perpendicular to the rest of the molecule.
• Thus the $\mathrm{H}-\mathrm{B}-\mathrm{H}$ bond angle are $90°\mathrm{C}$ and $120°\mathrm{C}$.
• And closest to it is option (B) $95°,120°$.
• Hence it is the correct option.

Therefore, In diborane the two H-B-H angles are nearly option (B) $95°,120°$.