108 WORK OF H. It. KREIDER. 



be the same as the ratio of the fluidities of these solvents. This, however, is not 

 the case. If the ratios between the values of /x^ for the salts in the two solvents 

 are not the same as the ratios between the values for the fluidities of these solvents, 

 the mass and probably the volumes of the solvated ions must differ in the two 

 different solutions. 



The fluidity of methyl alcohol at is 123.9, while that of ethyl alcohol is 56.24. 

 Since the fluidity of methyl alcohol is much greater than that of ethyl alcohol, we 

 would expect the ions of a dissolved salt to move much faster in methyl alcohol, 

 and, consequently, the conductivity of a solution of a salt at any concentration 

 would be much greater in methyl than in ethyl alcohol. At complete dissociation, 

 where the number of ions is the same in both solvents, we would expect the con- 

 ductivity in methyl alcohol to be as much greater than that in ethyl alcohol as the 

 fluidity of the former is greater than that of the latter. We would expect a direct 

 relation between fluidity and conductivity. 



Jones and his coworkers have shown that there is solvation in solutions in water, 

 methyl alcohol, ethyl alcohol, and solvents in general; and that this solvation 

 increases with dilution. From this we know that at complete dissociation solvation 

 is greater than at any dilution short of complete dissociation. 



Since a molecule of methyl alcohol is much heavier than one of water, the ion, for 

 equal solvation, would be loaded down more in the former solvent, and the conduc- 

 tivity in methyl alcohol would be less than in water, even if the fluidities were the 

 same. Again, the molecule of ethyl alcohol is heavier than the molecule of methyl 

 alcohol. The equally solvated ion would, therefore, be heavier in ethyl alcohol and 

 the conductivity less. 



Table 75 l gives the ratios of the fluidities of three solvents water, methyl alcohol, 

 and ethyl alcohol; also the ratio of /j, x for certain salts in these solvents at both 

 and 25. Water and eth3 r l alcohol are first compared. Their fluidities are nearly 

 the same, hence their ratio is nearly unity. The ratios between the values of ju* 

 for four salts in these two solvents are given. The mean of these values is 2.33 with 

 a minimum of 2.26 and a maximum of 2.44. This mean ratio of the values is much 

 greater than the ratio of the fluidity values of the two solvents, indicating that the 

 ion in ethyl alcohol moves much more slowly, compared with its velocity in water, 

 than we would expect from a comparison of the fluidities of the solvents. The only 

 explanation of this fact seems to be that the ion is loaded down much more in ethyl 

 alcohol than in water, and, hence, its velocity diminished, giving a much lower con- 

 ductivity. The only way in which it could be loaded down is by one or more 

 molecules of the solvent being united with the ion. 



In the second column of table 75 water and methyl alcohol are compared. The 

 fluidity of methyl alcohol is much greater than that of water. It is 2.18 times as 

 great at 0. There arc four jx x ratios. The mean is 1.03. The maximum is 1.05 

 and the minimum is 1.01. The fact that the fluidity of methyl alcohol is much 

 greater than that of water, while the conductivity of salts in methyl alcohol is but 

 little greater, indicates that in methyl alcohol the ion is loaded down more than in 



'The vn lues for /> of the various salts in water as a solvent given in table ""> are taken from the work of Jones and Getn.an 

 (Zeit, phys. Chem., 49, 3S5 (1904). 



