PHYSICO-CHEMICAL STUDIES OF COMPLEX FORMATION BETWEEN MOLYBDIC AND TARTARIC ACIDS. PART III. ULTRAMICROSCOPIC STUDIES ON THE CHANGE OF PARTICLE NUMBER AND CATAPHORETIC VELOCITY OF MOLYBDIC ACID SOL PARTICLES DURING COMPLEX FORMATION

That an appreciable portion of molybdic acid in its sol is present as true solution and also the presence of tartaric acid in the sol transforms the colloidal particles into solution, have been sbown by counting the number of particles per c.c. with an ultrami­croscope. The cataphoretic velocity of molybdic acid sol particles, either alone or in presence of tartaric acid at different pH has been studied and the results discussed