Rules for Electron Configurations
I was just about to do that. I have to warn you, though, that the rules may
seem arbitrary to you, and I won't be giving any satisfactory explanation of
the reasons for them. Partly that's because I want to spare you a lot of
complicated math, and partly it's because this is just the way nature is.
I'll just ask you to have faith that all this numerology comes out of a
sophisticated mathematical theory, and has been upheld time after time by
For now I think I'll be satisfied if you can tell me how to predict those
electron arrangements you've been showing me.
I can do that. First of all, you were correct when
you guessed that those colored rows in the chart correspond to the "main
energy levels"; they're often called primary energy levels,
incidentally. Usually, a higher row means a higher energy, and energy gaps
between rows tend to be quite large, in comparison with the gap between,
say, s and p.
Are you ever going to explain what s and p mean?
I'll do that right now. As you surmised, the s, p, and d
columns represent smaller "sublevels" of the primary rows...
Then why not just call them A, B, and C, or something else at least vaguely