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Homework Help: 1LoT, heat needed to raise the temperature of oxygen.

  1. Jan 22, 2009 #1
    1. The problem statement, all variables and given/known data
    A container holds 1.50 g of oxygen at a pressure of 9.00 atm.

    How much heat is required to increase the temperature by 108^\circ C at constant pressure?

    C_p (specific heat of oxygen for an Isobaric process) = 29.2

    2. Relevant equations

    1LoT for Isobaric process.
    Q=n * C_p * delta T

    3. The attempt at a solution

    So, plugging things in, with 1.5/16 to get the mols, got me to 295.65J. Plugging this in to the online homework system gave me a 'WRONG'. So trying different degrees for different sigfigs and rounding gave me nothing. So finally, it just gave me the answer... which was 148J, or almost exactly half of my calculations.

    So this leaves me with one of two issues. Either I plainly forgot something which was a divide by two, or the answer is half of what it should be. I want to know if I missed something big for two reasons:
    A. So I don't do it again.
    B. In case I am right, I can challenge my grade on this.

    On a side note, I haven't been here for a long time, so what is used these days to put in equations in the 'pretty format'. Is it still LaTex of something like that?
  2. jcsd
  3. Jan 23, 2009 #2


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    Homework Helper

    While converting in to mol, consider one molecule of oxygen, and its molecular weight is 32.
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