The Effect of Nonrandom Distribution of Molecules on the Equation of State for Gases

분자의 논랜덤 분포가 기체의 상태방정식에 미치는 영향

  • Received : 2013.08.03
  • Accepted : 2013.09.03
  • Published : 2013.10.20


Using the free volume of van der Waals equation, Carnahan-Starling equation for hard spheres, Wilson equation for nonrandom mixing of solution, NRTL equation and our equation, several new equations of states for pure gases are derived. Using these equations, compressibility factors for pure gases are calculated and compared with Nelson-Obert generalized compressibility factor charts. The equation of states using the concept of molecular nonrandom distribution gave better results than those of molecular random distribution. This shows that the molecular nonrandom distribution makes considerable effect on the equation of states.


Equation of state;Nonrandom distribution;Nonrandom mixing


  1. Hirschfelder, J. O.; Curtiss, C. F.; Bird, R. B. The Molecular Theory of Gases and Liquids; John Wiley & Sons: 1954.
  2. Prausnitz, J. M.; Lichtenthaler, R. N.; de Azevedo, E. G. Molecular Thermodynamics of Fluid-Phase Equilibria, 2nd ed.; Prentice-Hall: 1986.
  3. Guggenheim, E. A. Mixtures; Clarendon Press: Oxford, 1952.
  4. Wilson, J. M. J. Am. Chem. Soc. 1964, 86, 127.
  5. Flory, P. J. Principles of Polymer Chemistry; Cornell Univ. Press: 1953.
  6. Renon, H.; Prausnitz, J. M. AIChE J. 1968, 14, 135.
  7. Carnahan, N. F.; Starling, K. E. Equation of State for Nonattracting Rigid Spheres. J. Chem. Phys. 1969, 51, 635.
  8. Jung, H. Y.; Study of Excess Gibbs Energy for a Lattice Solution by Random Number Simulation. J. Korean Chem. Soc. 2007, 51, 312.
  9. Jung, H. Y.; A New Two-Parameter Equation of State for Pure Gases of Hard Spheres with an Attractive Potential. J. Korean Chem. Soc. 2012, 56, 207.
  10. Nelson, L. C.; Obert E. F. Generalized Compressibility Charts. Chem. Eng. 1954, 7, 203.
  11. Nelson, L. C.; Obert, E. F. Generalized PVT Properites of Gases. Trans. ASME. 1954, 7, 1057.
  12. Hill, T. L. An Introduction to Statistical Thermodynamics; Addison Wesley, Reading, Mass.: 1960.


Supported by : 덕성여자대학교