Graduado

solids. 6. Compare the orders of magnitudes of Prandtl numbers for gases and liquids. 7. Are the thermal conductivities of gaseous Ne20and Ne22 same? the 8. Is the relation ?, - ? = R true only for ideal gases, or is it also true for liquids? If it is not , true for liquids, what formula should be used? 9. What is the kinetic energy flux in the axial direction for the laminar Poiseuille flow of a New- 10. What is [P vl tonian liquid in a circular tube? = pv + [T vl for Poiseuille flow? ' See, for example, R. J. Silbey and R. A. Alberty, Physical Chemistry, Wiley, 3rd edition (2001), s2.11. Problems 287 PROBLEMS 9A.1 Prediction of thermal conductivities of gases at low density. (a) Compute the thermal conductivity of argon at 100°C and atmospheric pressure, using the Chapman-Enskog theory and the Lennard-Jones constants derived from viscosity data. Compare your result with the observed value1 cal/cm. s K. of 506 X (b) Compute the thermal conductivities of NO and CH, at 300K and atmospheric pressure from the following data for these conditions: . 9A.3. Estimation of the thermal conductivity of a dense gas. Predict the thermal conductivity of methane at 110.4 atm and 127°F by the following methods: (a) Use Fig. 9.2-1. Obtain the necessary critical properties from Appendix E. (b) Use the Eucken formula to get the thermal conductivity at 127°F and low pressure. Then apply a pressure correction by using Fig. 9.2-1.The experimental value2 is…