"S"^(2-):1s^2 2s^2 2p^6 3s^2 3p^6 A good starting point when looking for the electron configuration of an ion is the electron configuration of the neutral atom. In your case, the neutral atom is sulfur, "S", which is located in period 3, group 16 of the periodic table. Sulfur's has an atomic number equal to 16, which means that a neutral sulfur atom has a total of 16 electrons surrounding its ... More @Wikipedia
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