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Homework Help: Question about the derivative of Gibbs Energy

  1. Nov 6, 2008 #1
    1. The problem statement, all variables and given/known data
    There is a formula which says the change (delta) of volume of a mixture is equal to the partial derivative of delta G with respect to pressure at constant temperature. I don't understand how there can be a derivative and the delta used at the same time on G. I thought that derivatives were used for infinitesimal changes and that delta was used for larger ones.

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Nov 7, 2008 #2


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    Perhaps the delta signifies not the finite difference between values of G at different pressure or volume (which, as you said, would be improper to combine with differentials), but the finite difference between values of G for two separate phases of the same material.
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