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Van der waals gas

  1. Dec 10, 2006 #1
    i have to plot isotherms using the van der waals gas theory. i am using Maple to do this but no matter how many differant equations i use i cannot get the graphs to look right. it should look like a 1/x curve but with a sharpe trough in it, but all can get is a graph that looks like a normal 1/x curve. does anyone know the equation i should use to give me the curve of pressure against volume for differant values of temperature.
  2. jcsd
  3. Dec 10, 2006 #2


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    1. Henceforth, post such questions in the Homework & Coursework subforums.
    2. Write down the equation you are using to plot the isotherms
    3. What values have you assigned to the coefficients, b and a?
    4. You may simply be looking at the isotherms above the critical temperature. Have you chosen values of T that are very small?
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