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Homework Help: Energy required to ionize a hydrogen atom from n=1

  1. Feb 22, 2005 #1


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    We were given this formula in class:

    [tex]delta E= chR (\frac{1}{1^2} - \frac{1}{inf})[/tex]

    the [tex]1/1^2[/tex] is because it is in ground state. So the formula simplifies to

    c = 299792000
    h = 6.626E-34
    R = 10970000

    and [tex]1.60217653*10^{19} Joules / eV[/tex]

    I get:
    [tex]1.36009026784583 * 10^{-37} eV[/tex]

    The teacher did it in class and got 13.6 eV

    Same answer, just 38 magnitudes off :eek:

    What am I doing wrong?

    ** edit ** I figured it out. It's not 19, its -19 for Joules to eV
    Last edited: Feb 22, 2005
  2. jcsd
  3. Feb 23, 2005 #2


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    There you go:you have scientifically proven that [itex] 10^{-19} [/itex] and [itex] 10^{19} [/itex] are 38 orders of magnitude apart.Congratulations!!

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