JEE Main · 2024 · 06 Apr 2024 · Shift 2 · Chemical Bonding and Molecular Structure

(The stem's "$2p^2$" is a transcription artifact for "$s{p}^2$"; both the intended question and Allen's own solution concern $s{p}^2$ hybridisation.) Central-atom hybridisations: ${\text{NH}}_3$ is $s{p}^3$; ${\text{SO}}_2$ is bent, $s{p}^2$ (one lone pair on S); ${\text{SiO}}_2$ and ${\text{BeCl}}_2$ are linear, $sp$; ${\text{C}}_2{\text{H}}_2$ is linear, $sp$; ${\text{C}}_2{\text{H}}_4$, ${\text{BCl}}_3$, $\text{HCHO}$, ${\text{C}}_6{\text{H}}_6$ and ${\text{BF}}_3$ are planar/trigonal, $s{p}^2$; ${\text{C}}_2{\text{H}}_4{\text{Cl}}_2$ (1,2-dichloroethane) has $s{p}^3$ carbons. The $s{p}^2$ species are ${\text{SO}}_2,{\text{C}}_2{\text{H}}_4,{\text{BCl}}_3,\text{HCHO},{\text{C}}_6{\text{H}}_6,{\text{BF}}_3$ — six in total.