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Energy Level question (quantam physics)

  1. Dec 5, 2006 #1
    1. The problem statement, all variables and given/known data
    The hydrogen spectrum contains a blue line with a wavelength of 434 nm. Photons of blue light are emitted when hydrogen's electron drops from the fifth engery level to a lower energy level. What is the lower energy level?
    Given
    Wavelength = 434 nm
    n1 = 5
    n2 = ?
    R = 1.097 x 10^7 m^-1 (which i am not sure what this means or how to apply it but anyways)

    2. Relevant equations
    1/wavelength = R [ 1/n2^2 - 1/n1^2]


    3. The attempt at a solution

    1/434 = (1.097 x 10^7 m^-1) [1/n2^2 - 1/5^2]
    1/434 = (1.097 x 10^7 m^-1) [1/n2^2 - 1/25]
    0.0023 = (1.097 x 10^7 m^-1) [1/n2^2 - 0.04]
    0.0023 / (1.097 x 10^7 m^-1) = [1/n2^2 - 0.04]
    ((0.0023 / (1.097 x 10^7 m^-1)) +0.04 = 1/n2^2

    AND now im totally lost because it doesnt make any sense.. plug those values into your calculator and i get the exaxt same number for n2 as i started with n1 jeez!! SOMEONE HELP!! :eek:
     
  2. jcsd
  3. Dec 5, 2006 #2

    Kurdt

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    R is Rydbergs constant. You need to rearrange the equation you provided for n2.

    Remember that is 434nm aswell.
     
  4. Dec 6, 2006 #3
    does nm = Nanometers?
     
  5. Dec 6, 2006 #4

    Kurdt

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    Yes. 1nm = 1x10-9m
     
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