EOS Representation of Volumetric and Phase Behavior

Consider the plot of pressure versus total volume of a pure substance shown in Fig. 3.1. An equation of state (EOS) is desired to represent the volumetric behavior of the pure substance in the entire range of volume both in the liquid and in the gaseous state. It is also desired that the EOS be a continuous function of volume. 

Let us first examine the phase diagram of Fig. 3.1 at Tj, where 1 T. is the critical temperature. At point S, the liquid is 

The region between the spinodai curve and the saturated liquid curve may represent liquid in a superheated state. Similarly, the region 

Kenrick, Gilbert, and Wismer (1924) studied the superheating of a number of liquids at atmospheric pressure and found that there was a limiting temperature for each liquid, at or below which it always exploded. For example, the maximum value for the superheating of water at atmospheric pressure is around 270 0. Debenedetti (1996) presents metastability of water and other liquids in detail. 

It was mentioned that a point on curve AB may be at negative pressure. In other words, a liquid could have a negative pressure without 

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