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Van der Waals Equation, Virial Expansion

  1. Apr 11, 2014 #1
    1. The problem statement, all variables and given/known data

    Taken from Concepts in thermal Physics:


    2. Relevant equations

    3. The attempt at a solution

    Shouldn't the van der waal's equation be:

    [tex]p = \frac{RT}{V_m -b} - \frac{a}{V_m^2}[/tex]
    [tex]pV_m = \frac{VRT}{V_m -b} - \frac{a}{V_m}[/tex]
  2. jcsd
  3. Apr 11, 2014 #2


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    Yes. So (26.41) has a wrong sign. But it looks like they got it right in (26.42) and (26.43).
  4. Apr 11, 2014 #3
    You're right. It sure looks like they made a slew of algebra mistakes. The first term on the right hand side of 26.41 isn't even dimensionally correct.

  5. Apr 11, 2014 #4


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    Right. I didn't notice that they should not have had the factor of V on the left side of equation 26.41.

    Attached Files:

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