Question

In $BX_{3},B - X$ distance is shorter than what is expected theoretically because (X = F, Cl, Br, I)

• A. $sp^{3}$ hybridization of B is responsible for shorter B – X distance.
• B. B – X has a double bond character due to back – bonding
• C. Dimerisation takes place in $BX_{3}$ which is responsible for shorter B – X distance.
• D. Due to large size of X, B – X distance decreases.

Answer 1

Answer: (B)

B – X has a double bond character due to back – bonding

Answer 2

: Due to back – bonding, B – X in $BX_{3}$ has double bond character which because of resonance results in shorter B – X distance.