Final answer:
The important exceptions for S^2- are related to electron configurations in atoms, such as deviations from the normal rules of filling subshells. Exceptions to the octet rule in covalent bonding can also occur.
Step-by-step explanation:
The important exceptions for S^2- are related to electron configurations in atoms. According to the Pauli exclusion principle, no two electrons can have the same set of quantum numbers. This means that in some cases, the filling of subshells with electrons can deviate from the normal rules. Exceptions to the octet rule in covalent bonding can also occur, including incomplete octets, odd-electron molecules, and expanded octets.