OF CERTAIN SALTS IN TERNARY MIXTURES. 133 



Further evidence for this view is obtained from the 1-2-2 solvent, 

 whose specific conductivity exceeds by a much larger amount that cal- 

 culated by the method indicated above. The relative amounts of 

 acetone and water are much larger in the 1-2-2 solvent than in the 

 1-1-1; hence a larger dissociation of the glycerol would be expected 

 from the law of mass action. 



The viscosity and fluidity tables are arranged in groups under each 

 of the solvents. Thus, table 34 contains the data for rubidium bromide, 

 rubidium iodide, and ammonium iodide in the 1-2-2 solvent. A similar 

 arrangement is carried out for each of the seven solvents. Associated 

 with each table of viscosities is a corresponding table of temperature 

 coefficients, calculated by means of the formula given on page 122. 



It has been shown that negative viscosity coefficients occur in all 

 cases of rubidium salts in glycerol-water mixtures, and also for ammo- 

 nium bromide and iodide in these solvents. Such was also found to be 

 true in acetone-water mixtures, wherever the percentage of water was 

 higher than that of acetone. 



In the present investigation it appears that a similar behavior of 

 such salts manifests itself wherever the solvents are of the same general 

 nature as those mentioned above. Thus, negative viscosity coefficients 

 are to be observed in the case of all the salts studied in the 1-1-1, the 

 2-1-2, and the 2-1-1 solvents. Here it is evident that either gtycerol 

 or water, or both, are present in greater proportions than acetone. 

 Since glycerol is a solvent closely allied to water in its properties, we 

 may disregard its enormous viscosity and compare these solvents with 

 those acetone-water mixtures in which the water is present in the 

 larger proportion; these solvents would then correspond to 25, 20, 

 and 25 per cent acetone-water mixtures, in so far as the acetone affects 

 the tendency of the salts to lower the viscosity of the solvent ; while at 

 the same time, because of their glycerol content, they have viscosity 

 coefficients comparable with 50 to 25 per cent glycerol-water mixtures. 



On the other hand, we have those solvents in which the percentage 

 content of acetone exceeds either of the other two separately. Under 

 this head are included the 1-2-1 solvent and, in certain instances, the 

 solutions in the 2-2-1 mixture. 



In the case of the 1-2-2 and the 1-1-1 solvents an apparent fluctua- 

 tion is to be noted in the concentration curve for the various salts. 

 Thus, the more concentrated solutions increase the viscosity of the 

 solvent, while the more dilute lower it; a possible explanation of this 

 phenomenon is suggested later in discussing the conductivity data. 

 While this does not hold for all temperatures, it appears to be common 

 to all the salts studied. 



Tables 41 to 47 show the molecular conductivity, temperature coeffi- 

 cients in conductivity units, and percentages of ammonium iodide, 



