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Electronic transitions

  1. Oct 2, 2013 #1
    1. The problem statement, all variables and given/known data
    Which statement(s) is (are) FALSE in comparing the electronic transition from ni=5 to nf=2 in H with that of electronic transition from ni = 2 to nf = 5 in Be3+:

    a) The photon involved in the H transition lies in the visible spectrum while that involved in the Be3+ transition lies in the UV region of the spectrum.
    b) A photon of the same frequency is involved in both transitions, but it is emitted the H electron transition and absorbed in the Be3+ transition.
    c) All of the above.

    2. Relevant equations

    3. The attempt at a solution
    I've discarded b) as it is obviously false. However, i think the final answer it's c), but apparently statement a) is true. I know that the H transition corresponds to the visible light region, but why does the Be3+ one lie in the UV region? (if it is from n = 2?) Or how do transitions in absorption of photons work?
  2. jcsd
  3. Oct 3, 2013 #2


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    How do the energies (and thus also energy differences) in hydrogen like atoms depend on nuclear charge?
  4. Oct 3, 2013 #3
    As nuclear charge increases, shouldn't the energy transitions become higher in energy?
  5. Oct 4, 2013 #4


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  6. Oct 6, 2013 #5
    I'm extremely sorry for not replying! I had my exam the last day and i finally realized what was wrong. I did some calculations with the formula, plugging in the results and i got a result of 42nm (i really don't remember). As visible light is from 400nm-800nm, then it would be in the UV region of the spectrum!
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