Chemistry - CHEMICAL BONDING Question with Solution | TestHub

The correct option is ${\mathrm{O}}_2^{2-}$ This species has $18{\mathrm{e}}^{-}$, which are filled in such a way that all molecular orbitals are fully filled, so diamagnetic. $\sigma 1{\mathrm{s}}^2{\sigma }^{\ast }1{\mathrm{s}}^2,\sigma 2{\mathrm{s}}^2{\sigma }^{\ast }2{\mathrm{s}}^2,\sigma 2{\mathrm{p}}_{\mathrm{z}}^2,\pi 2{\mathrm{p}}_{\mathrm{x}}^2=\pi 2{\mathrm{p}}_{\mathrm{y}}^2,{\pi }^{\ast }2{\mathrm{p}}_{\mathrm{x}}^2={\pi }^{\ast }2{\mathrm{p}}_{\mathrm{y}}^2$ Hence, (A) is correct.