I have a question about the Aufbau principle. I was thinking first you fill up all the energy level 1 orbitals, then the energy level 2, then the energy level 3, etc., but that wasn't working out too well for me. Is THIS the order in which they will be filled?
1s
2s
2p
3s
3p
4s
3d
4p
5s
4d
5p
6s
4f
5d
6p
7s
5f
6d
7p
If so, how do you write the electron configuration? For example, I know that for nickel, it's 1s(^2)2s(^2)2p(^6)3s(^2)3p(^6)3d(^8)4s(^2)... but why wouldn't the 4s(^2) be written before the 3d(^8) since that orbital was "filled" first?
Lastly, I thought that all orbitals in a principal energy level must be filled with 1 electron, to give it a parallel spin, before you pair the electrons. If that is so, than how come, in phosphorus for example, 3s gets a pair of electrons, whereas 3d doesn't even have one? Am I getting mixed up and it's that all "electron slots" in an atomic orbit must have 1 electron before pairing them?
Please help and please explain well! THANKS
2007-02-22
04:45:55
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4 answers
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asked by
Happy
3
in
Chemistry