SO42- Octet Rule Exception Orbitals

[Zach Richardson 2f]

I am moderately confused on the So4(2-) Octet rule exception that Dr. Lavelle explained when he was talking about formal charge. I understand that because s has quantum number n=3 it can have s, p or d orbitals. However, I thought that the 4s would fill before the 3d and I'm not sure how that works with forming bonds. Do the 4s orbitals fill first even when sharing covalent bonds?

[Megan Sparrow 1A]

I believe you are on the right path in terms of 4s orbital filling first since it has lower energy compared to 3d orbitals. I'm not too sure about the covalent bonding aspect, but this problem and explanation I found online might help explain a bit.

[Olivia Smith 2E]

I believe the same rules for filling orbitals for the electron configuration is the same for when covalent bonding occurs. But orbitals are mainly just a conceptual way of looking at the electrons. So while an electron may be in the 4s or 3d orbital they may tend to stay on the outer cusp of the orbital when in a covalent bond as opposed to an atom's electrons that are not bonded at all.

[Andrew Wang 1C]

The 4s orbital is filled first before the 3d due to its lower energy. Although this isn't shown in our textbook's electron configurations, there is another way to order them called the "filling order" that shows this more clearly.

[Lily Mohtashami]

I believe that since 4s has lower energy than 3d it fills first but I also thought this was only true for a couple exception orbitals? Is this true for all molecules or elements?