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Homework Help: Isothermal Expansion

  1. Dec 5, 2004 #1

    I have what should be an easy problem, but I, of course, am having some issues.

    Here's the problem: The temperature of 2 moles if an ideal gas is 380 K. How much work does the gas do in expanding isothermally to 3 times its initial volume?

    So I know I'm gonna to need to use this equation to find the work done:
    [itex]W = nRT ln (\frac{V_f}{V_i})[/itex]

    I know that:

    n = 2
    R = 8.31
    T = 380
    Vi = (3)Vi
    Vf = ?

    I'm hung up on the volume portion of this problem. I don't have an initial or final volume and that's what I can't seem to work around. Any help would be greatly appreciated.

    Thanks in advance.
    Last edited: Dec 5, 2004
  2. jcsd
  3. Dec 5, 2004 #2
    Vi = Vi
    Vf = 3 Vi
    since it expands three times its initial volume
  4. Dec 5, 2004 #3
    plz correct vi=3.vi to be vf=3 vi, so now the problem is solved..
  5. Dec 5, 2004 #4
    W = nRTln(3)

    (Vf/Vi ) = 3Vi/Vi = 3
  6. Dec 6, 2004 #5
    Oh Lord. Something so simple that I couldn't put together. Thank you everyone for your reply. It is greatly appreciated. :)
  7. Dec 14, 2004 #6

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