Chemistry

Problem

Which of the following is the correct ground-state electron configuration for the oxide ion,

\text{O}^{2-}

? a)

1s^{2}\,2s^{2}\,2p^{4}\,3s^{2}

1s^{2}\,2s^{2}\,2p^{6}

1s^{2}\,2s^{2}\,2p^{4}

1s^{2}\,2s^{2}\,2p^{5}