Perspectives of Applicability and Validity of Tait Equation for Liquids

Abstract

Recently, a number of state equations for liquids have been proposed but none of them has a universal character (the possibility of application to all classes of liquids) as well as a sufficient theoretical basis and necessary accuracy. One of the most well-known empirical state equations of liquids is the Tait equation and its modified versions. A theoretical justification of the Tait equation does not exist despite numerous attempts to solve this problem. The authors have verified the Tait equation for aromatic hydrocarbons and nematic liquid crystals on the basis of experimental density data. The above mentioned studies allow concluding that the Tait equation can be used for prediction of the density over a wide range of pressures for different classes of liquids if the data taken from a narrow range of pressures are known. Theoretical justification of the empirical Tait equation is possible within the cluster model proposed by the authors.