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Homework Help: W_max & T in fuel cell

  1. Feb 13, 2009 #1
    1. The problem statement, all variables and given/known data

    2 H2(g) + O2(g) 2 H2O(l) K = 1.28e83

    As temperature increases, does the maximum amount of work obtained from the fuel cell reaction increase, decrease, or remain the same?

    2. Relevant equations

    1. G = -RTln(K)
    2. dG = dH - tdS
    3. w_max = dG

    3. The attempt at a solution

    Okay, using formation values, I calculated that for this reaction, both dH and dS are < 0.

    If dG = w_max (eq. 3), then w_max = -RT ln K (1 and 3)
    Since ln(K) is positive, the larger the T, the more negative w_max.
    Thus, as T increases, w_work decreases?

    Is that right? Thanks.
  2. jcsd
  3. Nov 24, 2016 #2


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    Science Advisor
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    Gold Member

    Sounds good.
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