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2A.19 7th edition

Posted: Wed Oct 31, 2018 8:01 pm
by Katie Frei 1L
Hello! Could someone please explain to me why for part e) of this question the electron configuration of Ni^+2 is [Ar]3d^8 instead of [Ar]3d^6 4s^2. Thank you!

Re: 2A.19 7th edition

Posted: Wed Oct 31, 2018 9:13 pm
by Lumbini Chandrasekera 1B
I think it [Ar] 3d^8 because lower principle energy levels should be filled with electrons first before the next energy level (n=4) is filled which is why it wouldn't be [Ar] 3d^6 4s^2.

Re: 2A.19 7th edition

Posted: Thu Nov 01, 2018 11:35 am
by Nicole Lee 4E
Electrons are removed from the 4s orbital before 3d electrons are removed, so you get [Ar]3d^8 instead of [Ar]3d^6 4s^2.

Re: 2A.19 7th edition

Posted: Thu Nov 01, 2018 2:24 pm
by Theodore_Herring_1A
The electrons are removed from the 4s orbital before 3d when forming ions. This is because electrons are always removed from the outermost orbital first, in this case 4s. This is why it is [Ar]3d8 and not [Ar]3d64s2.