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Homework Help: Finding Final Volume - almost got it

  1. Jan 25, 2005 #1
    Ok, here is what is given:

    1.00 mol O2
    Ti = 300K
    Vi = 5.00L
    4400 j of energy transfered by heat to the system
    Vf = ?
    Constant Pressure = 29.4 J/mol * K

    So I set the problem up using Q = n(Constant Pressure)(Tf - T-i)
    Solving for Tf I find that Tf is equal to 449.7K.

    Then using equation (Vf - Vi) = (nR(Tf - Ti)) / P

    Vf = ((1.00mol * 8.31 J/mol*K * 149.7K) / (1.013*10^5 N/m^2)) + 5.00L

    I am getting Vf = 17.28 L

    Can anyone tell me what I am doing wrong? My teacher told me the answer should be 7.52, could he of possibly meant 17.52?

    Any help would be appreciated!
  2. jcsd
  3. Jan 25, 2005 #2


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    Homework Helper

    1.The teacher is right.
    2.The final temperature u computed is right...

    3.The formula u used is wrong...

  4. Jan 25, 2005 #3


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    Homework Helper

    This is the specific heat capacity, not pressure.
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