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Definition of Gas Constant

  1. Jul 16, 2009 #1
    I wonder what's the meaning of Gas constant, R.
    I have read it in Wikipedia, but i still cannot understand.
    Could you please tell me some concept about R's definition?

    Thank you very much for your information.
  2. jcsd
  3. Jul 16, 2009 #2


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    There's no great meaning behind it. We have an arbitrary set of units as far as the universe is concerned, so when we try to do things like calculate temperature based on pressure and volume, we need to take this into account by scaling by a certain amount.
  4. Jul 16, 2009 #3
    Experiment shows that for a gas at low pressure PV is proportional to T ,therefore PV= a constant times T.If 1Kg of gas is considered then the constant has different values for different gases but if 1 mole is considered then the constant,R,has the same value for all gases(hence the name........universal molar gas constant)
  5. Jul 16, 2009 #4
    I think you answered my question.
    Can I read it as R is an experimental coefficient about the gas/vapour/other stuff which relates to the interaction of PV with T from Molar Mass point of view>?
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