Concise Physical Chemistry

c02 JWBS043-Rogers September 13, 2010 11:23 Printer Name: Yet to Come

34 REAL GASES: EMPIRICAL EQUATIONS

p, bar

0 20 40 60 80 100

pV,

dm

3 bar

24.3

24.4

24.5

24.6

24.7

24.8

FIGURE 2.11 Cubic real gas behavior.

Problem 2.15

(a) What is the volume of one mole of CO 2 at 366 K andp=111 bar according

to the ideal gas law?

(b) The critical temperature of CO 2 is 305.1 K. The critical pressure and volume

of CO 2 are 73.8 bar and 0.0956 dm^3 (Laidler and Meiser, 1999). If a compress-

ibility factor of 0.68 is read from a chart of isotherms, what is the reduced

volume of one mole of CO 2 at 366 K andp=111 bar according to the chart?

(c) The van der Waals parameters for CO 2 area= 3 .66 andb= 0 .0429. What

is the volume of one mole of CO 2 at 366 K andp=111 bar according to the

van der Waals equation?

(d) What is the volume of one mole of CO 2 at 366 K andp=111 bar according

to the corresponding states equation? What is the volume?

(e) The critical constants for helium areTc= 5 .3K,pc= 2 .29 bar, andVc=

0 .0577 dm^3 mol−^1. What is the volume of one mole of He at 7.95 K and

p= 2 .75 bar according to the corresponding states equation? What is the

volume?