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Molecule N2o4 has a greater entropy than NO2

  1. Nov 28, 2008 #1

    a.a

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    1. The problem statement, all variables and given/known data

    Why is this statement false?

    'Two moles of a substance at temperature T and pressure p has twice the entropy of one mole of the same substance at the same temperature and pressure.'
    --> Is it because the number of moles doesn't matter. Why doesn't it?

    Why is this statement true?

    'The entropy change for the reaction N2O4(g) -> 2 NO2(g) is positive.'
    --> The molecule N2o4 has a greater entropy than NO2, so it delta S, change in entropy would be entropy of NO2 - entropy of N2O4, which would be a negative (smaller - bigger number)? Am I going about this wrong?
     
  2. jcsd
  3. Nov 28, 2008 #2

    Mapes

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    Re: Entropy



    It's not false; entropy is an extensive variable.
     
  4. Nov 29, 2008 #3

    a.a

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    Re: Entropy

    If there are more moles in the same place under the same tempreature and pressure, wouldn't that decrease the entropy?
     
  5. Nov 29, 2008 #4

    Mapes

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    Re: Entropy

    Nope.
     
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