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Homework Help: Work calculation for isothermal compression

  1. Feb 20, 2012 #1
    1. The problem statement, all variables and given/known data

    2. Relevant equations
    Work done by an ideal gas, isothermal process: W=n*R*T*ln(V_f / V_i)
    Work, constant-pressure process: W=p*(V_f - V_i)

    3. The attempt at a solution
    I first tried plugging n=1, R=8.31, T=273.15, V_f=17.5 L, V_i=24 L into the first equation and it didn't work.

    I then tried the constant-pressure formula with the corresponding values given from the problem (p=.937 atm, V_f=17.5 L, V_i=24 L) and it didn't work either.

    This problem seems pretty straight forward but I can't get the right answer. Help?
  2. jcsd
  3. Feb 20, 2012 #2


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    Homework Helper

    The work formula you used is for the work of the gas. The problem asks the work of an external agent. Is the external work positive or negative?

    The data given are not consistent with the ideal gas law. 1 mol oxygen at 0 °C can not have 24 L volume at 0.937 atm pressure. Have you copied it correctly?

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