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Cyclic heat machine

  1. May 10, 2008 #1

    When this machine takes 0.2 moles of a one atomic ideal gas through this cycle, find the pressure and volume in 1, 2 and 3

    OK, I start by finding V1 by using the ideal gas law. 4,92 L
    This is also V2 of course.

    Next, using the ideal gas law again, I find that P2 is 2 atm, or 203 kPa.

    We know that P3 is 1 atm, so I try to find V3 with the ideal gas law:

    V3 = nRT3/P3 = 0.2*8.3145*455/(101.3*10^3) = 7.47L

    This answer is, however, wrong. The correct answer is 7.94L. What is my mistake?
    Last edited by a moderator: Apr 23, 2017
  2. jcsd
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