Question

Among ${NO}_3^{-},As{O}_3^{3-},{CO}_3^{2-},{ClO}_3^{-},{SO}_3^{2-}$ and $B{O}_3^{3-}$, the non-planar species are

• A. $C{O}_3^{2-},S{O}_3^{2-},B{O}_3^{3-}$
• B. $As{O}_3^{3-},Cl{O}_3^{-},S{O}_3^{2-}$
• C. $S{O}_3^{2-},N{O}_3^{-},B{O}_3^{3-}$
• D. $S{O}_3^{2-},C{O}_3^{2-},Cl{O}_3^{-}$

Answer 1

The correct option is B $As{O}_3^{3-},Cl{O}_3^{-},S{O}_3^{2-}$

Species Hybridization Geometry Number of lone pairs

$N{O}_3^{-}$ $s{p}^2$ Trigonal planar Zero

$As{O}_3^{3-}$ $s{p}^3$ Pyramidal One

$C{O}_3^{2-}$ $s{p}^2$ Trigonal planar Zero

$Cl{O}_3^{-}$ $s{p}^3$ Pyramidal One

$S{O}_3^{2-}$ $s{p}^3$ Pyramidal One

$B{O}_3^{3-}$ $s{p}^2$ Trigonal planar Zero

$As{O}_3^{3-},Cl{O}^{-3}$ and $S{O}_2^{-3}$ have $s{p}^3$ hybridization and hence are non-planar species, while $N{O}_3^{-},C{O}_2^{-3}$ and $B{O}_3^{-3}$ have $s{p}^2$ hybridisation and hence are planar species

Hence, option B is correct.