Answer
$1s^{2}$$2s^{2}$$2p^{4}$
$1s^{2}$$2s^{2}$$2p^{6}$ or $[Ne]$
Work Step by Step
Write the electron configuration for an uncharged O atom. Two electrons must be added to O to form the ion $O^{2-}$. Add these electrons to its energy level and change the corresponding electron configuration.
