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Jason Ko
- 16
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I'm recently studying Bohr's model. My textbook claims that only low-pressure gases emit a line spectrum while solids, liquids and high-pressure gases emit light with a continuous range but why?
How exactly does the change of energy level result in a continuous spectrum? Could you please explain it in detail?mfb said:Nearby atoms influence the energy levels in atoms, lowering or raising them a bit. In a low pressure gas this can be negligible, in solids and liquids it's very important.
The Pauli Exclusion Principle says that no two atoms can have precisely the same quantum levels and we never look at just one atom. The precise energy level of a system will be affected by more than the 'simple' fields that the theory suggests for a single atom; nearby atoms affect each other and the more and the closer they are means a (albeit narrow) range of energy states exists and lines 'broaden'.Jason Ko said:only low-pressure gases emit a line spectrum
And there I was, thinking that the Pauli Exclusion Principle dictated that no two electrons (generally fermions), within a quantum system (one atom), could share the same quantum state at the same time.sophiecentaur said:The Pauli Exclusion Principle says that no two atoms can have precisely the same quantum levels and we never look at just one atom.
The point is (imo) that there are more "quantum systems" than just single atoms. As soon as two atoms get within range of each other you have a quantum system. We were told about Pauli in the simple context of the Hydrogen atom and that system can be described by just four quantum numbers. Bring two or more atoms near each other and the total number of quantum numbers needed to describe the system 'fully' increases as the potential energy between them becomes significant. Molecular Hydrogen has a much more complicated spectral line structure.Baluncore said:And there I was, thinking that the Pauli Exclusion Principle dictated that no two electrons (generally fermions), within a quantum system (one atom), could share the same quantum state at the same time.
Just cos you can't see it, doesn't mean it's not happening. Glass is a transparent solid and you can see photons released inside it.Baluncore said:Photons emitted by a solid, or by a dense gas or plasma, do not tend to escape to be seen