The 6 hydrogen spectral line series'

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    Hydrogen Line Series
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Discussion Overview

The discussion revolves around the hydrogen spectral line series, specifically the classification of these lines into six series based on the principal quantum number (n) and their corresponding regions in the electromagnetic spectrum. Participants explore the relationship between these series, the Bohr model's energy shells, and the energy transitions that result in the emission of spectral lines.

Discussion Character

  • Exploratory, Technical explanation, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether "n" refers to the principal quantum number and how the series relate to the energy shells of the Bohr model.
  • Another participant references the Rydberg formula, clarifying the roles of n_1 and n_2 in electron transitions.
  • A participant asserts that the n=1 series corresponds to spectral lines emitted as electrons transition to the first energy shell and queries why these emissions are in the UV region.
  • A later reply challenges the assumption that the energy emitted from higher transitions (n=6 to n=2) would be greater than from lower transitions (n=2 to n=1), explaining that energy levels are not equally spaced and providing calculations to support this.
  • One participant expresses understanding after the clarification regarding energy differences between transitions.

Areas of Agreement / Disagreement

Participants express differing views on the energy emitted during electron transitions and the implications of the energy level spacing, indicating that the discussion remains unresolved regarding the nuances of energy differences in spectral emissions.

Contextual Notes

There are limitations in the discussion regarding assumptions about energy level spacing and the implications of the Rydberg formula, which are not fully explored or resolved.

Horseb0x
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I noticed that the hydrogen spectral lines are grouped into 6 series and given a value for n. I also noticed that each series was named after its discoverer but "coincidentally?" falls into a specific region of the EM spectrum so the Lyman series (n=1) of lines are all in the UV region, the Balmer series (n=2) in the visible region, the Paschen series (n=3) the IR region etc. Firstly is this "n" the principle quantum number? If so what have these series' got to do with the different energy shells of the Bohr model? For example what has the balmer series got to do with the 2nd energy shell? Finally what is it about this correlation that causes the lines of each series to appear where they do. For example why do the lines all appear in the UV region when n=1 but lie in the visible region when n=2?
 
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See the Rydberg formula for hydrogen. n_2 is the principal quantum number ("energy shell number") of the atom before a transition. n_1 is the principal quantum number of the atom after a transition.
 
So the n=1 series is all the spectral lines emitted by electrons as they fall back to the 1st energy shell. Why do they all emit UV radiation? If the energy emitted is the energy difference between the 2 energy levels then it makes sense that Lyman lines are higher in energy than Balmer lines but the photon emitted by an electron dropping from n=6 back to n=2 would he higher in energy than say n=2 back to n=1 wouldn't it?
 
Last edited:
Horseb0x said:
but the photon emitted by an electron dropping from n=6 back to n=2 would he higher in energy than say n=2 back to n=1 wouldn't it?

No, it wouldn't, because the levels aren't equally spaced. Try plugging in the numbers. The energy of an n=2 to n=1 photon is 13.6eV(1/1-1/4) = 10.2eV. The energy of an n=6 to n=2 photon is 13.6eV(1/4-1/36) = 3.02eV.
 
Ah right, that explains it. Thanks a lot!
 

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