Question

In which of the following pairs of molecules/ions, the central atoms have $sp$${}^2$ hybridization?

• A. $NO{{}_2}^{-}$ and $NH$${}_3$
• B. $BF$${}_3$ and $NO{{}_2}^{-}$
• C. $NH{{}_2}^{-}$ and $H$${}_2$$O$
• D. $BF$${}_3$ and $NH{{}_2}^{-}$

Answer 1

Answer: (B)

$BF$${}_3$ and $NO{{}_2}^{-}$

For an atom to have $s{p}^2$ hybridization it's a steric number $\left(SN\right)$ must be $3$

$SN$ of an atom is the sum of the total no. of sigma bonds and the lone pairs of that atom

Structure of the given molecules:

(Image)

$\therefore N{O}_2^{-}$ and $B{F}_3$ molecules have $s{p}^2$ hybridized central atoms.