A new general state equation of real gases

A new general state equation for all real gases is proposed based on the theory that the inelastic collision leads the gas molecules to liquefy on the walls of container, thereby affords the exchange of heat between the gas and the surrounding via boundary. Therefore, the state equation of gas is equivalent to the equation of gas-liquid phase equilibrium. Based on the Boltzmann distribution of energy, a new general state equation is established. Moreover, in the critical region, the gravimetric potential is introduced to the state equation. P-V-T data at saturation and isobars of 79 substances are applied for fitting the equation. The fitting results are applaudable. Furthermore, the state equation is applicable for the gas-solid phase equilibrium. A calculation result indicates that the critical region starts from ca. 30-40% and ends with ca. 60-70% of the molar fraction of liquefied portion, irrespective of the molecular mass and interactions. Hence, the critical temperature and extraordinarily large specific heat capacity as well are resulted from the interruption of heat exchange circuit between gas and the surroundings. Academically, the new state equation lays a base-stone for the derivative equations of gas specific heat capacity, sound velocity in the gas, etc.