WORK OF H. R. KREIDER. 107 



Table 74 gives the conductivity of lithium bromide in methyl alcohol. At 

 complete dissociation probably is reached at 6,400 liters. At 25 there is no maxi- 

 mum in conductivity, but the rate of increase is much smaller above 3,200 liters 

 than it is at greater concentrations, indicating that the maximum is nearly reached. 



Table 74 gives the conductivity of lithium bromide in ethyl alcohol. At there 

 is complete dissociation at 3,200 liters. At 25 it is complete at 6,400 liters. For 

 both temperatures at higher dilutions the conductivity remains almost constant up 

 to a dilution of 102,400 liters, where, at 25, there is a marked decrease in the con- 

 ductivity. 



Table 74 gives the conductivity of potassium sulphocyanate in methyl alcohol. 

 This is a repetition of work previously done. We have now obtained more con- 

 cordant results. Here, complete dissociation is reached at both temperatures at 

 3,200 liters. 



Table 74 gives the conductivity of cobalt bromide in both methyl alcohol and 

 ethyl alcohol. Here, there is no maximum in conductivity. This is probably due 

 to the fact that cobalt bromide is much solvated. 



Table 75 gives the ratios of the values of fx M for a number of salts in the following 

 solvents: Water and ethyl alcohol, methyl alcohol and water, and methyl alcohol 

 and ethyl alcohol. When we consider the large magnitude of the experimental error 

 in working at these great dilutions, it is quite probable that the relation ju k for one 

 solvent /{jl^ for another solvent = c, holds where the salts have approximately the 

 same degree of solvation. 



That there is a constant relation between the values of fX M for different salts in 

 different solvents we would expect. When a certain salt in two different solvents is 

 completely dissociated, we have either the same number of ions present or, relative 

 to the concentration, the same number of ions present. 



When the point of complete dissociation is reached at the same dilution in both 

 solvents, we have the same number of ions present in the same volume of the two 

 solvents. When such a point of complete dissociation exists at different dilutions 

 in solutions of the two solvents, the number of ions in equal volumes of the two 

 solutions varies directly as the concentration, and we have, relative to the concen- 

 tration, the same number of ions present. 



Conductivity is a function of the number of ions present and the velocity with 

 which these ions move. Since, at the complete dissociation of a salt in solutions 

 of two different solvents the number of ions is actually the same, or relative to the 

 concentration the same, we can eliminate this factor the number of ions and 

 consider only the velocities with which these ions move. 



Two factors primarily determine ionic velocity, the ionic mass and volume, and the 

 fluidity of the solution, which is, of course, the reciprocal of the viscosity. Assum- 

 ing that the ionic masses and volumes of a certain salt in two different solvents at 

 complete dissociation remain the same, then the velocities of the ions ought to vary 

 as the fluidities of the respective solvents. Since the number of ions in the two 

 solvents at the same dilution of the solutions is the same, the ionic masses and 

 volumes being the same, the conductivities ought to vary directly as the fluidities 

 of the solvents; the ratio between the values of fx in the various solvents ought to 



