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Homework Help: When doing calculations, should pressure be in atm or Pa?

  1. Nov 23, 2006 #1

    Lee

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    When doing calculations, should pressure be in atm or Pa? (looking for answers in joules)
     
  2. jcsd
  3. Nov 23, 2006 #2
    Doesn't matter AFAIK as long as you adjust the constants for example R in PV=nRT.
     
  4. Nov 23, 2006 #3

    Lee

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    Good'o. I jsut wanted to double check.
     
  5. Nov 23, 2006 #4
    Use Pascals. P = F / A, Force is usually given in Newtons amd 1 Pa = 1 Nm^-2.

    edit: should read the thread title, good practice anyway :).
     
    Last edited: Nov 23, 2006
  6. Nov 24, 2006 #5
    all you need is to have is consistant units.
    pressure in Pa, volume in cubic meters and R = 8.3145 J mol^-1 K^-1
    then work will be in joules
     
    Last edited: Nov 24, 2006
  7. Nov 24, 2006 #6

    dextercioby

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    Science Advisor
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    Always choose the path with the least number of conversions.

    Daniel.
     
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