## Electrons and photons [ENDORSED]

manasa933
Posts: 72
Joined: Fri Sep 29, 2017 7:04 am

### Electrons and photons

Suppose the energies of levels are as follows:

n=1, E=-13.6 eV
n=2, E=-3.4 eV
n=3, E=-1.51 eV

A photon of energy 11 eV, which is slightly greater than the difference between the energies of level 1 an 2, will the electron jump to the 2nd level from the first or will it remain in the 1st level as the energy supplied isn't exactly equal to the difference in energy between the two levels? If it does jump to the first level, where does the remaining energy go?

Chem_Mod
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Joined: Thu Aug 04, 2011 1:53 pm
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### Re: Electrons and photons  [ENDORSED]

As I discussed in class the photon energy has to match the energy level difference.
If there is no match then the photon is not absorbed. Instead it 'passes through'.

I also discussed this is what makes glass windows transparent to light in the visible region.
Glass does not have electronic transitions in the visible region, therefore visible light passes through glass.

I encourage discussion of this in student groups, in discussion section, peer learning sessions, office hours, on Chemistry Community, etc.