What elements contains a full third energy level and what element contains the first p electron??
Here is an interactive site that will show you how the 1s, 2s, 2p, etc levels fill. Post your answers here if you want someone to check them. Also, you need to clarify what you mean by a third energy level if you repost. Is that the d electron level or the n=3 level? Anyway, your answers are on the site below.
http://www.iun.edu/~cpanhd/C101webnotes/modern-atomic-theory/aufbau-principle.html
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