Page 1 of 1

Question about 4s and 3d orbitals

Posted: Thu Oct 25, 2018 9:35 am
by Bingcui Guo
I know that 4s shows lower energies than 3d orbital so the electrons will fill the 4s first. But why after 2e- occupied the 4s orbitas, 4s states lower energy?

Re: Question about 4s and 3d orbitals

Posted: Thu Oct 25, 2018 11:32 am
by Daniel Lai
The 4s orbital is only less in energy when there are no electrons in 3d. But, once 4s and 3d are filled, 4s is higher in energy, so it is the first to lose electrons.