If the gas were ideal, the parameter b would vanish from Eq (6.29), and Eq (3.14) would be recovered.
Example: N2 (y = 1.4) is compressed isentropically from 0.1 MPa and 20oC (state 1) to 10 MPa (state 2). Find the final temperature if (a) nonideality is characterized by the Van der Waals EOS with a = 0.14 J-m3/mole2 and b = 3.9x10-5 m3/mole and (b) ideality is assumed
(a) In state 1, N2 is very nearly ideal, so v1 = 2.44x10-2 m3/mole. However, v2 cannot be immediately calculated because it depends on T2, which is also an unknown. The EOS is written for the conditions of state 2, solved for T2 and equated to the right hand side of Eq (6.29). The result is:
Solving the second equality numerically yields v2 = 9.4x10-4 m3/mole and the first equality gives T2 = 1098 K.
Was this article helpful?
Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.