4.7: Work and Heat Have a Simple Molecular Interpretation
- Page ID
- 390808
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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 \(\delta w_{rev} = -PdV\)
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:
Once again we can find an important quantity of our system by manipulating the partition function \(Q\).