Answer Happy

3. (20 pts) Plotting the van der Waals EOS (Numerical problem). Write a computer program and use it to make plots of isotherms for two different fluids listed in Baierlein Table 12.1. Your plots should resemble Baierlein Fig. 12.9, except the axes will be labeled in physical uinits. • Baierlein Table 12.5 shows the constants a,b for the fluids listed in Table 12.1. These a,b values were calculated using Eqs. 2 above. I prefer to use SI units (J rather than eV for energy) because that way the pressure will automatically come out in Pa. Alter- natively, you can start with the critical temperature and pressure listed in Table 12.1 and use these to compute a, b. • The horizontal axis should be v = V/N (volume per particle). Suitable units could be 10-30 m • The vertical axis should be p (physical pressure). Suitable units could be atm, bar, or MPa. 2 • The range of your plots should be similar to Baierlein Fig. 12.9, going up to about three times the critical v and twice the critical temperature. • Your plots should show several isotherms, including the critical isotherm (solid lines in Fig. 12.9). You do not need to include the dashed line showing the two-phase region, but it would be good to plot a dot at the critical point. • The van der Waals equation is only good for the immediate vicinity of the critical point. I found that it gave negative pressures if I plotted an isotherm for a temperature less than about 0.85TC.