Question

Which of the following statements is(are) correct regarding $B{F}_3$:

• A. $B{F}_3$ is covalent
• B. $B{F}_3$ is a colourless gas
• C. The bond lengths in $B{F}_3$ are significantly shorter than the sum of the covalent radii
• D. $p_z$ atomic orbital on $B$ does not involve in hybridization

Answer 1

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

$p_z$ atomic orbital on $B$ does not involve in hybridization

The boron halides are covalent. $B{F}_3$ is gaseous, $BC{l}_3$ is liquid and $B{I}_3$ is solid.
The bond lengths in $B{F}_3$ are $1.30{\text{A}}^{\circ }$, are significantly shorter than the sum of the covalent radii
($B=0.80{\text{A}}^{\circ },F=0.72{\text{A}}^{\circ })$.
The empty $2p_z$ atomic orbital on $B$ which is not involved in hybridization is perpendicular to the triangle containing the $s{p}^2$ hybrid orbitals.