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How to express van der waals equation as virial expansion?

  1. Feb 7, 2009 #1
    1. The problem statement, all variables and given/known data

    Express the van der Waals equation of state as a virial expansion in powers of
    1/Vm and obtain expressions for B and C in terms of the parameters a and b.
    (Hint. The expansion you will need is (1–x) -1 = 1+x+x2+... . Series expansions
    are discussed in Appendix 2 of Atkins.)
    Measurements on argon gave B=-21.7 cm3.mol-1 and C=1,200 cm6.mol-2 for the
    virial coefficients at 273 K. What are the values of a and b in the corresponding
    van der Waals equation of state?

    2. Relevant equations
    Van der waals equation of state : ( p + a / V^2 ) ( V-b ) = RT

    3. The attempt at a solution
    Apparently this question is very common and found throughout the web. But I couldn't find any solution. I don't even know how to begin with expressing ;(
    please help. thanks.
  2. jcsd
  3. Feb 7, 2009 #2
    Solve for P giving you a term containing


    Factor out Vm then use the hint.
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