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Entropy Proof Question

  1. Feb 27, 2010 #1
    1. The problem statement, all variables and given/known data

    Using the exact differential, state function characteristics of S prove that ΔS for step I is always > 0 for an ideal gas expanding adiabatically and irreversibly from point 1 at TA,PA to point 2 at TB,PB

    can anyone help me with this one?
    A key difference this one has over others is that temperature is varied and thus not a normal adiabatic process where it mirrors an isothermal one

    2. Relevant equations

    first law, second law, helmholtz and gibbs free energy equations? mayb

    3. The attempt at a solution

    I basically got the same outcome as a adiabatic irreversible expansion identical to a isothermal equation but have a feeling the assumptions leading up that are wrong
  2. jcsd
  3. Feb 27, 2010 #2


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    Homework Helper
    Gold Member

    Hi wangchungman, welcome to PF!:smile:

    We can't tell you whether what you did was wrong or or not unless you actually show what you did.... Post your calculations and explain in detail any assumptions your are making.
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