1. The problem statement, all variables and given/known data Using a strict interpretation of the n+l rule, how many protons would an atom need to create a ground state electron configuration with one electron in a 5g orbital? Give electron configuration. 2. Relevant equations 3. The attempt at a solution g is an l value of 4, 4+5 = 9. So 5g is filled after other orbitals with n+l's lower than 9, or equal but with higher n values. This puts 5g after 9s, does it not? I have no clue what to do from here.