The Ideal Gas EOS

Ch 2, Lesson E, Page 2 - The Ideal Gas EOS

• Here is your trusty old friend, PV=nRT, piv-nert !
• As I explained back in Lesson C, it isn’t very practical to use the total volume when we are trying to compare the behavior of different substances and different systems.  We need to use the molar volume instead.
• When we rearrange the Ideal Gas EOS, we find that P-V-wiggle equals RT.  From now on, when I refer to the Ideal Gas EOS, this is the form I am talking about.
• I suspect you remember that R is the Universal Gas Constant.  You may even recall the value of this constant from your Freshman chemistry classes..  If you do, you most likely remember the 1st value shown here because it has the units commonly used in Freshman chemistry: L, atm, gram-moles and Kelvins.
• The Universal Gas Constant has the same meaning and uses in other systems of units, but different values.  Here is the value of R in a few common engineering systems of units.
• These will are become very familiar to you as you work your way through this course.
• The chapter 2 First Aid Kit contains values for R in a wide variety of units.
• OK, so we have this tool, but we still don’t when it is accurate.
• Hmmm………..