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Homework Help: Calculate number of molecules

  1. Jun 3, 2010 #1
    can anyone tell me how i should approach this problem

    calculate the number of molecules of air in a beach ball of volume 6.0*10^-2m^3. The air is at temperature 35degrees, a pressure of 1.1*10^5Pa and can be trested as an ideal gas.

    i just want to know what area of classical physics it is
    Last edited: Jun 3, 2010
  2. jcsd
  3. Jun 3, 2010 #2


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    Its is Thermodynamics, and you should apply the Ideal gas law.

  4. Jun 3, 2010 #3
    thankyou, i did manage to work it out as follows


    k beint the boltzmann constant
    T being temperature in Kelvins and
    N = number of molecules and P and V pressure and volume

    rearange N=PV/kT

    simples :)
  5. Jun 3, 2010 #4


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    Good job!
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