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Homework Help: Energy Level Diagram

  1. Mar 26, 2007 #1
    1. The problem statement, all variables and given/known data
    A monatomic gas is illuminated with visible light of wavelength 400nm. The gas is observed to absorb some of the light and subsequently emit visible light of both 400nm and 600nm. The initial state is -5.0 eV and the ionized atom (continuous energy levels) is 0 eV.
    a) Draw the situation.
    b) If the inital state of the atoms has energy -5 eV, what is the energy of the state to which the atoms were excited by the 400nm light?
    c) At which other wavelength(s) outside the human visible range do these atoms emit radiation after they are excited by the 400nm light?

    2. Relevant equations

    3. The attempt at a solution
    I wasn't in class when my teacher covered the material, and it's not in the book.
    Can someone at least just get me started, explaining the drawing and what equations I should use?
  2. jcsd
  3. Mar 26, 2007 #2
    Anyone? Anyone?
  4. Mar 26, 2007 #3
    try a post on the chemistry board.
  5. Mar 27, 2007 #4
    But it's physics, AP physics actually. I've asked a few chem buds and they don't get it.
  6. Mar 27, 2007 #5
    well you can calculate the energy of the photon from e=hv where v=frequency and of course c=f*lambda, different frequencies will be absorbed, the highest being that required to strip the electron (ionize) away= 5eV; alternatively, radiation is emitted in the form of a photon when an electron changes to a lower energy orbital. there should be scads of material online covering this as well as the calculations of these. heres one of hundreds: http://zebu.uoregon.edu/~soper/Light/atomspectra.html [Broken]
    Last edited by a moderator: May 2, 2017
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