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Clarification on R constant?

  1. Mar 7, 2012 #1
    Clarification on "R" constant?

    I'm pretty confused right now. The R constant, or universal gas constant has been troubling me. In one problem it is defined as .0821 L*atm/m*K. But soon after that it becomes 8.314 J/mol*K. Can somebody explain this concept to me? Thank you.
  2. jcsd
  3. Mar 7, 2012 #2
    Re: Clarification on "R" constant?

    J is defined in terms of m3 and Pa. So convert L -> m3 and atm -> Pascals to get the new value of R.
  4. Mar 8, 2012 #3


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    Staff: Mentor

    Re: Clarification on "R" constant?

    Value depends on the units used, just like traveling at 62 mph and 100 km/h is the same thing. See the table on the right: http://en.wikipedia.org/wiki/Ideal_gas_constant
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