Abstract:
It is known that heat capacities at constant volume C[inf V] can be calculated by using the relation connecting C[inf V] with values of sound velocity for these substances [A. J. Matheson, Molecular Acoustics (Wiley, London, 1971)]. The relation for calculating C[inf V] for mixtures following the lattice model of regular mixtures in the zero quasichemical approximation [I. Prigogine, The Molecular Theory of Solutions (North Holland, Amsterdam, Interscience, New York, 1957)] on the basis of some data including sound velocity referring to the pure components has been derived. The analogous problem for mixed solutions, namely for the solutions containing several solutes, has been solved. The relation for calculating C[inf V] for a mixed solution consisting of the solvent and one of the solutes and having the same solvent chemical potential value (which the considered mixed solution has), follows the same conditions.