Find the number of molecules having two lone pairs on the central atom.

(i) ${\mathrm{I}}_3^{+}$ (ii) ${\mathrm{XeF}}_2$ (iii) ${\mathrm{XeF}}_4$ (iv) ${\mathrm{H}}_2\mathrm{O}$ (v) ${{\mathrm{NH}}_2}^{-}$ (vi) ${\mathrm{H}}_2\mathrm{S}$ (vii) ${\mathrm{H}}_2{\mathrm{SO}}_4$ (Viii) ${\mathrm{NF}}_3$

Which of the following species are hypervalent?

$1$. ${\mathrm{ClO}}_4^{-}$

$2$. ${\mathrm{BF}}_3$

$3$. ${\mathrm{SO}}_4^{2-}$

$4$. ${\mathrm{CO}}_3^{2-}$

Consider the following statements:

${\mathrm{S}}_1$: ${\mathrm{N}}_2{\mathrm{H}}_4$ is pyramidal about each $\mathrm{N}$ atom.

${\mathrm{S}}_2$: ${\mathrm{NH}}_2\mathrm{OH}$ is pyramidal about the $\mathrm{N}$ atom and bent about the $\mathrm{O}$ atom.

${\mathrm{S}}_3$: ${\mathrm{CH}}_3\mathrm{COCl}$ is trigonal about the carbon atom (attached to $\mathrm{O}$ and $\mathrm{Cl}$).

Out of these, select the correct one.