Tracer diffusion in liquids

This work is divided into two sections. The fir s t details the measurement of intradiffusion coefficients by conventional diaphragm -cell technique. Isotopic friction coefficients have been calculated from the intradiffusion, mutual-diffusion, and activity data for the systems; Sucrost labelled sucrose-water and Mannitol-labelled mannitol-water. An attempt has been made to correlate friction coefficients with molecular properties. Because of the limited data available for system s of the type studied good correlations w ere not obtained. The second section describes the development of a continual monitoring technique applied to the diaphragm cell. In an effort to improve the accuracy of this technique a large number of tracer-ion concentration measurements were made on the system Strontium chloride - water. The results obtained from continual monitoring w ere com pared with those from the conventional technique and the capillary -cell technique. Good agreement between diffusion coefficients from the three methods was not obtained and an analysis of the errors involved in the methods has been made to explain the discrepancies