Hi Geodome,
Is there any other name of electron configuration outer shell beside "full" and "half-fill"? For example, of K+: we call "full", but that is not an atom so someone call it as "un real full", is that right?
I also have this question: I understand that Ar is "full" but I wonder the way you explained. If the energy level between 3p and 3d is so big so how could S in H2SO4 has +6 oxidation number? It must in high energy state with 1 electron in 3s subshell, 3 electrons in 3p and 2 more in 3d.