94 



CONDUCTIVITY AND VISCOSITY IN MIXED SOLVENTS. 



Tables 55 and 56 (figs. 28 and 29), for potassium iodide in mixtures of 

 acetone and methyl alcohol, show that the conductivity is almost exactly 

 what we should expect from the law of averages. There is, however, a slight 

 tendency towards a maximum as we raise the temperature. In this respect 

 the results are similar to those obtained with lithium nitrate. The values 

 for the conductivity of potassium iodide in pure water, and ethyl and methyl 

 alcohols, were taken from the work of Jones and Lindsay. 



140 



50$ 75$ 



Percentage of Acetone 



100$ 



FIG. 29. CONDUCTIVITY OF POTASSIUM IODIDE IN MIXTURES 

 OF ACETONE AND METHYL ALCOHOL AT 25. 



Tables 56 and 57 (figs. 30 and 31) show the same characteristics for 

 potassium iodide, in mixtures of acetone and ethyl alcohol, as those observed 

 for the same salt in mixtures of acetone and methyl alcohol, but there is less of 

 a tendency towards a maximum. In fact, there is a slight sagging in the 

 curves. It is observed that this statement is almost identical with the one 

 in regard to lithium nitrate in mixtures of acetone and ethyl alcohol. 



Tables 55 and 56 (figs. 32 and 33), for potassium iodide in mixtures of 

 acetone and water, display a minimum in molecular conductivity. There is 

 no tendency towards a maximum. It should, however, be noticed that the 

 divergence of the curves between the 75 per cent mixture and pure acetone is 

 small. The salt is, therefore, quite largely dissociated at all dilutions in all 

 of the mixtures. 



It was thought advisable, at this stage, to use solutions of sodium iodide 

 in the various mixtures. Solutions of sodium iodide in acetone had been 

 investigated by Carrara, 1 by Dutoit and Friderich, 2 and by Jones. 3 It was 



1 Gazz. Chim. Ital., [1] 27, 207 (1897). 



2 Bull. Soc. Chim., [3] 19, 334 (1898). 



s Amer. Chem. Journ., 27, 16 (1902). 



