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Calculate the frequency, in hertz (level n = 10 to level n = 5)

  1. Sep 19, 2009 #1
    Calculate the frequency, in hertz, of the photon that is emitted when a electron falls from level n = 10 to level n = 5 in the H atom.

    Enter a numeric answer only, no units.

    I tried asking in other places but ppl are so ambiguous about it.
    :( please help me.

    I used rydberg formula:
    1/λ = RH ∙ (1/n₁² - 1/n₂²)
    (RH rydberg constant for hydrogen, n₁ lower level, n₂ higher level)

    λ = 1/ [ 1.09678×10⁷m⁻¹ ∙ (1/5² - 1/10²) ] = 3.0392×10⁻⁶m

    and then I converted to Hz = 9.89e14 but i still GOT IT wrong :( Please help me someone!!!
  2. jcsd
  3. Sep 19, 2009 #2
    The above calculation is done for a hydrogen atom. Check the problem to see if a different Z is given. (the factor of [tex]Z^2 [/tex]is added to the rydberg equation for approximating photon frequencies of hydrogen-like atoms with a different atomic number.
  4. Sep 19, 2009 #3
    I don't understand. So there's another Z? But I thought it is only 5 and 10?

    oh dear. i think i posted in the wrong section.
    (please move this thread) thanks!
    Last edited: Sep 19, 2009
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