Equation of state and related properties of light and heavy waters and their mixtures

In this paper we have shown that the p—V—T measurements for light and heavy water systems can be represented with sufficient accuracy by the logarithmic form of the two parameter Tait equation. One of the parameters, which is dimensionless, turns out to be the same for both types of water. We make the plausible assumption that even for their mixtures this parameter has the same value. The other parameter can then be determined from the limiting isothermal compressibility which is obtainable with great precision from the speed of sound measurements at normal pressure. The p—V—T data for the water mixtures can thus be generated by using the Tait equation. This simple equation is very useful in the determination of the values of those thermodynamic functions which are not easily accessible to direct experimental measurements at elevated pressures. Lastly the principle of corresponding states is shown to be applicable for the two water systems.