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DQ = −TdS(produced)

  1. Apr 9, 2010 #1
    1. The problem statement, all variables and given/known data

    (a) Show that dU < TdS − PextdV , using the first and second laws, for an infinitasimal spontaneous process
    in an open system.
    (b) Thus dU < 0 could be viewed as a criterion for spontaneity at constant S, V . Show that dQ = −TdSproduced in
    such a process. Is heat absorbed or lost in a constant S, V process?

    2. Relevant equations

    3. The attempt at a solution
    I did part (a) easily enough. I just included it for background information.
    I'm having troubles with the idea that d(bar)Q = -TdS(produced) since the 2nd law of thermodynamics says d(bar)Q = TdS.
    Any help with this would be great. Thanks!
  2. jcsd
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