1. The problem statement, all variables and given/known data 1) How do you know when an atom can have an expanded octet? 2) Is there a maximum number of electrons that an expanded octet can hold? If there is, how do I know what that max. number is? 2. Relevant equations N/A 3. The attempt at a solution 1) My textbook is giving me conflicting information. It says: - Only atoms with d orbitals can expand their octets - Atoms with an atomic number of 12 or more can expand their octets. But, what about sulfur? It has no d oribtal, but it has an atomic number of 16! So which of the above is the actual rule? Electron config for sulfur: 1s2 2s2 2p6 3s2 2p4 2) Um... I'd guess yes. Using sulfur as an example again, its expanded octet could only hold six bonds (because 2 + 4, from 3s2 2p4, is 6). Is that true?