ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Cryoscopy in Solvents with Dystectic Melting

I. Proks, V. Daněk, M. Chrenková, F. Šimko, and Z. Pánek

Institute of Inorganic Chemistry, Slovak Academy of Sciences, SK-842 36 Bratislava

E-mail: uachdane@savba.sk

Received: 11 June 2001

Abstract: Theoretical derivation of relations valid for cryoscopic measurements in solvents with dystectic mode of melting, i.e. solvents, which undergo at melting a more or less extended thermal dissociation, when chemical reaction between solvent and solute takes place, is presented. When one of the products of this chemical reaction is identical with the product of thermal dissociation of the solvent, the problem of defining the number of “foreign” substances, originating in the reaction between the solvent and the admixture arises. The presented approach shows that the partially dissociated solvent cannot distinguish originating own dissociation products as foreign substances, which made it easier to determine the nature of the probable chemical reaction. The presented approach is applied in the systems Na₃AlF₆—Al₂O₃, Na₃AlF₆—Fe₂O₃, and Na₃AlF₆—Al(PO₃)₃, which are of great importance in the fundamentals of aluminium electrolysis.

Full paper in Portable Document Format: 562a71.pdf

Chemical Papers 56 (2) 71–76 (2002)