Answer:
1s^2 2s^2 2p^6 3s^2 3p^6
Explanation:
Number of electrons = Number of protons. Originally, sulfur has 16 protons, but the question asks states 2- ions. So S^(2-), or a total of 18 protons. Follow the rules, and make sure the exponents add up to 18. 2 + 2 + 6 + 2 + 6 = 18 electrons.