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19.7: Work and Heat Have a Simple Molecular Interpretation

  • Page ID
    13705
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    Statistical interpretation

    We can use what we know about the statistical side of thermodynamics to give a simple interpretation to a change \(dU\):

    we see that because \(\delta w_{rev} = -PdV\)

    Image:CH431_Image67.gif
    Image:CH431_Image68.gif

    See also section 17-5 :In this section it is shown that we can manipulate the partition function to find the pressure of a system by calculating the above moment of the distribution. Again we take the derivative of the logarithm of the partition function \(Q\), this time versus V and show that the result resembles the last equation pretty closely (apart from a factor ). Thus we get:

    Image:CH431_Image69.gif
    Image:CH431_Image70.gif

    Once again we can find an important quantity of our system by manipulating the partition function \(Q\).


    19.7: Work and Heat Have a Simple Molecular Interpretation is shared under a CC BY-NC-SA 4.0 license and was authored, remixed, and/or curated by LibreTexts.

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