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Thermodynamics - Gibbs Free Energy Question

  1. Apr 7, 2010 #1
    1. The problem statement, all variables and given/known data
    I'm having some difficulty with this question, not exactly sure how to start it. Any suggestion would help. Thanks

    At 2.02 atm water boils at 121 °C. Calculate the change in the Gibbs free energy
    when one mole of steam at 121 °C and one atm condenses to liquid water at the
    same temperature and pressure. Is this process possible? Assume that steam
    behaves as an ideal gas and that the density of liquid water at 121 °C is constant
    at 942 kg m-3.

    2. Relevant equations
    I think these equations are useful

    dGT=VdP [1]
    dΔGT = ΔVdP [2]
    ΔGp2 = ΔGp1 + int(ΔVdP) [3]

    and since it is an ideal gas

    PV=nRT -> V=nRT/P [4]

    Now I think subbing [4] into [2] or [3] would help but not sure how to get ΔGp1?
  2. jcsd
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