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Homework Help: Ideal gas unit conversions

  1. Aug 28, 2011 #1
    [SOLVED] Ideal gas unit conversions

    1. The problem statement, all variables and given/known data

    The ideal gas constants used in this text are typically mass-based: kJ / (kg*K). It is more useful to have them in units of kJ / (kmol*K). How to convert them using data from this text?

    2. Relevant equations

    3. The attempt at a solution

    I'd think that this is a problem in which I'd consult the periodic table to obtain the molecular mass of a given compound, but the P. table is not included. I have steam tables, gas-constant/critical point properties tables, etc. Seems like such a simple question, yet I'm not seeing the path. Can anyone point me in the right direction?
    Last edited: Aug 28, 2011
  2. jcsd
  3. Aug 28, 2011 #2


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    You have a computer. Surely you can find a periodic table somewhere on the internet.
  4. Aug 28, 2011 #3
    Yes, obviously. I also have numerous chemistry books. But the problem specifically states to use data contained within the text--there is no periodic table within. Hence, my confusion.

    Converting grams to moles is trivial with a PT. Without the PT; I don't understand...
  5. Aug 28, 2011 #4
    Nevermind, I found a table in the text that lists molecular masses of some selected compounds. The problem is reduced to triviality, afterall.

    Wouldn't it be much simpler to just include a PT on the frontsheet or at least appendix, like every other science book I've encountered? What kind of Thermodynamics book wouldn't include one? Silly!

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