1the explanation given is
E.C of Ni is 1s2,2s2,2p6,3s2,3p6,4s2,3d8
so E.C. of Ni2+ is 1s2,2s2,2p6,3s2,3p6,4s0,3d8
so no. of unpaired electrons are 2
Why are the elctrons removed from 4s?
4 Answers
1
1357Because 4s is the outermost shell
and electrons goes from the outermost shell as they are at greater distance from nucleus
1but 3d is filled after 4s.........so electron should go from 3d ?
1the energy of 4s orbitals is less than 3d...
however, after filling of 4s subshell, energy of 3d decreases than 4s and next electrons are fileed there.now, as the energy of 3d subshell is less than 4s, so, the electrons will be removed from 4s orbital first instead of 3d...
i hope this is clear...