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Hydrogen spectral lines

  1. Mar 13, 2012 #1
    When a completely ionized atom of hydrogen captures an electron, the latter may conceivably cascade toward the nucleus by jumping successively from one permitted orbit to the next.
    If we could watch the light emitted by this single atom, to what lines of the complete hydrogen spectrum will the last four jumps correspond?
  2. jcsd
  3. Mar 13, 2012 #2


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  4. Mar 13, 2012 #3
    i cannot get the exact explanation from that link... please help me.
  5. Mar 13, 2012 #4


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    Do you know the 4 lowest orbital energy levels ?
  6. Mar 14, 2012 #5
    then what are those?
  7. Mar 14, 2012 #6


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    This is the beginning of Quantum Mechanics. The fact that atoms can only exist in certain energy states and that they can only be excited to jump between those states accounts for the line spectra that they produce (and absorb).
    The explanation is not just available in one paragraph.

    QM had to be invented to explain away the fact that an electron in orbit (under acceleration) should, classically, be radiating energy constantly. This would cause its orbit to decay (like a satellite in a dense atmosphere). It doesn't. It goes on and on and on. You can 'explain' this by assuming that the electron, in this 'bound state' behaves like a wave. QM follows from this - along with line spectra etc. etc..
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