Question

The $BC{l}_3$ is a planar molecule whereas $NC{l}_3$ is pyramidal because

• A. $B-Cl$ bond is more polar than $N-Cl$ bond
• B. $N-Cl$ bond is more covalent than $B-Cl$ bond
• C. nitrogen atom is smaller than boron atom
• D. $BC{l}_3$ has no lone pair but $NC{l}_3$ has a lone pair of electrons

Answer 1

Answer: (D)

$BC{l}_3$ have $s{p}^2$ hybridisation and no lone pair of electron on central atom but $NC{l}_3$ have $s{p}^3$ hybridisation and also contains one lone pair of electron on nitrogen, so $BC{l}_3$ is planar.