A crucial incorrect understanding in the traditional solution theory

Abstract

In this work, thermodynamically we demonstrate that the partial molar volume of a substance in a mixture always is positive. Therefore, in the past hundred years, the obtained so-called partial molar quantity of a solute within the framework of the traditional solution theory all were not the real partial molar quantity of the solute because the obtained limiting partial molar volumes of many electrolytes in water within the framework of the same theory were negative. The comparative study shows that hydrophilic molecules, especially ions in solvents such as water have been chemically solvated, no more naked because few solvent molecules in the traditional so-called first solvation shell of the molecule have belonged to the molecule.