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Ideal gas laws

  1. Jan 29, 2009 #1
    How do you combine two separate volumes of an ideal gas wich are at different temperatures pressures and volumes and then work out the change in internal energy?
    I have been trying to get my head around this without success.
  2. jcsd
  3. Jan 29, 2009 #2
    It has been a while since I used this, but:

    total energy (T)=potential energy (P)+ kinetic energy (K)
    I forgot the actually variable symbology you are probably using.

    T1=P1+K1; T2=P2+K2
    Tcombined= P1+P2+K1+K2

    that simple I think.

    If your asking how would you combine the volums of gas it would probably depend on what type of experiment you are doing and the type on energy in the system you are trying to analyze.
  4. Jan 29, 2009 #3
    I am considering a closed system that contains two different sized chambers chambers separated by a barrier each chamber has the same ideal gas in different volumes, temperature and pressure.
  5. Jan 29, 2009 #4

    How will the two volums interact? will you open a valve of is the plate separating them flexible? Actually, it probably doesn't matter. Simple calculate the total energy of each system and combine them for the total evergy of all systems. If you are assuming no interaction with outside world, then this will work. even if you have a negative pressure and a positive pressure that are equal in magnitude (and all the other variables are equal) you might think the total energy should be zero, and it should, since one will have negative pressure and the other positive pressure. All the energy of each system would be release by the transfer.
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