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another topscore GC question

Discussion in 'DAT Discussions' started by SayitIsntSO, Jul 29, 2006.

  1. SayitIsntSO

    SayitIsntSO Member
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    I thought when you are finding the change in enthalpy for a rxn you go: pdt-reactants? I am confused by the topscore solution in which you gotta find the change in enthalpy for: 2C(s)+O2(g)---> 2CO (g). I would try to rewrite the question, but it's too hard. For anyone who has topscore, i think you know this question. It is on test 2 for genchem, I think question 57 (gchem 17). I would really appreciate the help.
     
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  2. dat_student

    dat_student Junior Member
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    If you post the question I may be able to help :) I don't have TOPSCORE
     
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  3. Pdiddy310

    Pdiddy310 Med School 4.0
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    I could be wrong b/c it's been several years since I've taken gen chem but...

    If I remember correctly, the heat of formation of elements in standard state is 0. Depending on whether or not the C(s) is diamond or graphite in this question, you will get a different answer.

    The equation should look like this:

    [2 x enthalpy of CO] - [2 x enthalpy of C(s) + 0]
     
  4. R.L.H

    R.L.H LoVe mY liFE
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    i think you are right, b/c the heat of formation of elements in standard state (O2 (g) in this case) is 0.
     
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  5. dontbam

    dontbam Member
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    g
     

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