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Homework Help: Saha Equation

  1. Feb 7, 2014 #1
    In the picture, I have the question and the Saha Equation.
    I have all the correct answers for all the variables and constants on the right side of the equation, and I've done the calculation twice, and I'm getting an answer of 1.56x10-28
    That is equal to the left side, which is NII/(NI+NII).
    NII are ionized hydrogens and NI are neutral hydrogens.

    Edit: Actually, after looking at it, what is the left side of that equation? It's not NII/(NI+NII), is it? The text of this book had me thinking it was.

    The question indicates that almost all of the hydrogens will be ionized in the core of the sun, but that means I'm supposed to be getting an extremely large number, not an extremely small one. My answer indicates that almost all of the hydrogens have not been ionized. I don't see a way around that given this equation.


    Attached Files:

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  2. jcsd
  3. Feb 8, 2014 #2
    Ok after looking at an example in the book, I think I need to put that tiny number into NII/(NI+NII)

    With NII being the ionized hydrogen, and NI being neutral hydrogen. But getting that extremely small number says that I have almost zero ionized hydrogens, which makes no sense. Do the units make sense in this equation? I think there's no way that the small number I got is correct.
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