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Homework Help: Heat Transfer

  1. Oct 11, 2009 #1
    Hey everyone, I'm new to the forums here and just have a question.

    1. The problem statement, all variables and given/known data
    A piston-cylinder device contains a mixture of .2kg of H2 and 1.6kg of N2 at 100kPa and 300K. Heat is now transferred to the mixture at constant pressure until the volume is doubled. Assuming constant specific heats at the average temperature, determine (a) the heat transfer and (b) the entropy change of the mixture

    3. The attempt at a solution
    My multiple attempts included using equations from examples in the chapter. The only thing with the example is that its with air and not H2 or N2. I dont know if this really makes a difference but I've tried m C deltaT to find the heat and gotten an answer of around 29kJ but my understanding of the problem is that I'm looking for the flow of the heat transfer in kJ/min which involves using the partial pressure and specific humidity. The main thing I'm lacking in that process is the I have no flow in kg/min. Any help would be much appreciated.

  2. jcsd
  3. Oct 12, 2009 #2


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    Science Advisor
    Homework Helper
    Gold Member

    Hi Synergyx 26, welcome to PF. Please show your calculations if you'd like others to comment; right now there's no way to know what you've tried.

    What assumptions can you make about the gases involved that might help you to extract a temperature change?

    Humidity and flow are not relevant factors in this problem.
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