What is the electron configuration of ferrous?

Answer 1

Fe3+=1s2 2s2 2p6 3s2 3p6 3d5

You might think that it should me ...... 4s2 3d3...this is incorrect..

your argument may be that....3d sub shell has more energy than 4s sub shell...& therefore,electrons from 3d,should be removed 1st.

This happens when there are no electrons in shells.....when the sub shells are filled with electrons,it change.Hence,after electrons are filled in orbitals,4s electrons have more energy than 3d electrons...

so, the electron config. of Fe3+=...3p6 3d5........not 4s2 3d3

Here...2 electrons are removed from 4s and 1 electron is removed from 3d....therefore,it makes Fe3+ ion..

Answer 2

Fe^2+ : [Ar]3d^6 Nutral iron is [Ar]3d^6 4s^2 Fe^2+ : [Ar]3d^6 (The 4s orbital electrons take less energy to remove and go first) Fe^3+ : [Ar]3d^5 (this gives a half filled stable d orbital)

Answer 3

[Ar]3d^6 4s^0