By combining the van der Waals’ equation of state and the Free Length Theory of Jacobson, a new theoretical model is developed for the prediction of internal pressure of pure liquids and liquid mixtures. It requires only the molar volume data in addition to the ratio of heat capacities and critical temperature. The proposed model is simple, reliably accurate and capable of predicting internal pressure of pure liquids with an average absolute deviation of 4.24% in the predicted internal pressure values compared to those given in literature. The average absolute deviation in the predicted internal pressure values through the proposed model for the five binary liquid mixtures tested varies from 0.29% to 1.9% when compared to those of literature values.
International Letters of Chemistry, Physics and Astronomy (Volume 5)
N. Santhi et al., "Estimation of Internal Pressure of Liquids and Liquid Mixtures", International Letters of Chemistry, Physics and Astronomy, Vol. 5, pp. 1-7, 2012