Physics Forums
Still some days of holidays left. 
Back in school, I've must have been 14 years old or something. Our teacher showed that different substances emits different coloured light. From the top of my head I remember copper - green and sodium - yellow. He showed more, but these will do for now.
Sodium has a valence electron in 3s. Let's say I want to check whether it is the jump from 3s to 3p and back that creates photons of this yellow wave length. Now I get puzzled. from my understandings the jump between energy levels are the source of the light.
\displaystyle E_n = -\frac{13.6}{n^2}
But this doesn't explain why the 3p orbital is at lower energy than 3s. Since \displaystyle -\frac{13.6}{3^2} = -\frac{13.6}{3^2}
I don't know whether I should be embarrassed by missing the obvious or flinch back because it's so complicated. How do I calculate the frequency of a jump from 3p to 3s..?
Back in school, I've must have been 14 years old or something. Our teacher showed that different substances emits different coloured light. From the top of my head I remember copper - green and sodium - yellow. He showed more, but these will do for now.
Sodium has a valence electron in 3s. Let's say I want to check whether it is the jump from 3s to 3p and back that creates photons of this yellow wave length. Now I get puzzled. from my understandings the jump between energy levels are the source of the light.
\displaystyle E_n = -\frac{13.6}{n^2}
But this doesn't explain why the 3p orbital is at lower energy than 3s. Since \displaystyle -\frac{13.6}{3^2} = -\frac{13.6}{3^2}
I don't know whether I should be embarrassed by missing the obvious or flinch back because it's so complicated. How do I calculate the frequency of a jump from 3p to 3s..?