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Homework Help: Termo physics nr1 help

  1. Nov 3, 2011 #1
    1. The problem statement, all variables and given/known data

    In 2 identical containers we have equal mass of helium and Argon at the same temperature.The ratio of the 2 pressures (pressure 1 and pressure 2) knowing that μ helium= 4 kg/kmol and μ argon= 40 kg/kmol is:
    a 0.1 b 10 c 5 d 40 e 1/5

    2. Relevant equations
    i dont know


    3. The attempt at a solution
    i dont know
     
  2. jcsd
  3. Nov 3, 2011 #2
    What macroscopic equation gives the behaviour of ideal gases?
     
  4. Nov 3, 2011 #3
    idk tell me
    i got bad marks at physics
     
  5. Nov 3, 2011 #4
    idk =?
     
  6. Nov 3, 2011 #5
    pv=nrt?
    i dont know man physics is not my main thing
     
  7. Nov 3, 2011 #6
    pV=nRT

    Correct.

    Now see what is identical in both cases and hence try to see on what physical quantity does p depend.
     
  8. Nov 3, 2011 #7
    p=nrt/v
    ?
    can you please give more hints?
     
  9. Nov 3, 2011 #8
    Temp is the same for both.
    What else is the same?
     
  10. Nov 3, 2011 #9
    R constant and T
    n is the quantity
    EDIT:Was joking man i know how to do it p1v=m/miu RT
     
    Last edited: Nov 3, 2011
  11. Nov 3, 2011 #10
    Correct.
    But if you read the problem CAREFULLY you will notice that there is something else constant.
     
  12. Nov 3, 2011 #11
    HAHAAHAH man now i dont understand
    p1v=U x R
    ??
     
  13. Nov 3, 2011 #12
    Which gas has the bigger volume?
     
  14. Nov 3, 2011 #13
    Argon i think.
     
  15. Nov 3, 2011 #14
    is the argon in a bigger container?
     
  16. Nov 3, 2011 #15
    no. what to do?
     
  17. Nov 3, 2011 #16
    Each gas in an IDENTICAL container. Hence the volume ...
     
  18. Nov 3, 2011 #17
    Ok so volume is constant.Here is what i made so far.
    Find p1 and p2
    P1=1/μ helium *R
    P2=1/μ argon *R

    and then P2/P1 = 10.

    so from those answers: a) 0.1 b)10 c)5 d)40 e)1/5

    the right one is b?
     
  19. Nov 3, 2011 #18
    P argon/P helium = 0.1
     
  20. Nov 3, 2011 #19
    P helium/P argon = 10
     
  21. Nov 3, 2011 #20
    so its 10?
    i did it good?
    can you help me at the other problem too? :D
     
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