A STUDY OF THE COEXISTENCE OF THE LIQUID AND GASEOUS STATES OF AGGREGATION IN THE CRITICAL TEMPERATURE REGION. ETHYLENE

Abstract

The coexistence curve of ethylene has been determined in a manner similar to that described in a previous investigation on ethane (9). It is found to lie entirely within the coexistence curve determined by P-V-T methods by other investigators (6). This is considered to be evidence for the formation of a dispersion of liquid and vapour before the critical temperature is reached. The term "critical dispersion temperature" is suggested for the temperature at the apex of the coexistence curve determined by the disappearance of the meniscus in a bomb shaken in the manner described in this investigation. The apex of the curve determined by P-V-T methods is the true critical temperature, beyond which liquid is not stable. The classical critical temperature, determined by the disappearance of the meniscus in a stationary bomb, is an indefinite point between these two.