DETERMINATION OF PARTIAL MOLAR VOLUMES FOR BINARY SOLUTIONS VIA EXCESS MOLAR VOLUMES

Abstract

An alternative procedure of estimating partial molar volumes for binary sulutions is proposed. Although the concept of the partial molar volume is important in physical chemistry, the method of its estimation has been mainly introduced in textbooks, as a graphical procedure, namely, a method of intercepts. Such a graphical method often yields imprecise values. Instead the partial molar volumes can be derived via the corresponding excess molar volumes using the Redlich-Kister equations. Moreover, the values are evaluated for the ethanol-ethylene glycol and t-amyl alcohol-toluene solutions at25℃ using the available data measured by Loucks. It has been found that our alternative procedure provides more precise partial molar volumes than Loucks', and is useful for general binary solutions. These findings will help chemistry students learn the meaning of partial molar volume.