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Homework Help: Pressure and Kinetic Energy of Gases

  1. Dec 3, 2005 #1
    Hi Everyone,

    I just have a quick question about pressure and kinetic energy of gases. Say you have 3 identical flasks filled with 3 different gases, Flask A contains CO at 760 torr Flask B contains N2 at 250 torr and Flask C contains H2 at 100torr and all three flasks are at a temperature of 0.0 degrees celsius. In which flask will the molecules have the greatest kinetic energy? I was thinking that the flask with the highest pressure (A) will have the most kinetic energy, but the fact that each flask contains a different gas makes it a bit more difficult. I'm assuming that because the flasks are identical there are an equal number of moles of each gas. Which do you guys think would have the greatest kinetic energy?
  2. jcsd
  3. Dec 4, 2005 #2


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    Gold Member

    Do you know what temperature means?

    I think thats the key here...
  4. Dec 4, 2005 #3


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    Science Advisor

    Is one of the constraints that there is an equal amount of mass in each flask?
  5. Dec 4, 2005 #4
    They don't say anything about the mass being equal in all the flasks, the question is listed word for word as it appears in the book. There is another option to say that there is not enough information to say which flask has the highest kinetic energy, which I am leaning towards at this point because no matter what equation I look at to try and see what would have the highest energy it seems like I am missing a variable (usually moles).
  6. Dec 4, 2005 #5
    Lol temperature is the average kinetic energy of a substance. Therefore all flasks have the same kinetic energy. Thank you.

    So the pressure of the flask and the substance in the flask have no influence on the kinetic energy at all?
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