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Homework Help: Heat question

  1. Mar 15, 2009 #1


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

    If you have on mole of He atoms and one mole of O2 and add the same amount of energy to both, which underges the greater change in temperature? In which case are the particles, on average, moving faster.

    2. Relevant equations


    3. The attempt at a solution

    I reasoned that for the first problem He would undergo the greater change in temp. since it has fewer degrees of freedom and all the energy goes into random translational kinetic energy. For the second problem I reasoned that the He particles must be moving faster because the have more KE and are less massive than O2 molecules. Would someone mind letting me know if my reasoning is correct? Thanks.
  2. jcsd
  3. Mar 16, 2009 #2

    Andrew Mason

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    Right on both points if by "more KE" you mean "more translational KE". The O2 and He molecules each have the same amount of kinetic energy if the same amount of energy is added to each and if they are kept separate.

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