520 
IOWA ACADEMY OF SCIENCE Vol. XXIV, 1917 
No minimum is to be observed. It is, therefore, evident that 
lithium chloride behaves abnormally in each of these solvents. 
Conductivity measurements indicate that the concentration ratio 
of the ions approaches the value 10. Electromotive force meas- 
urements, on the other hand, indicate that the activity ratio of 
the ions decreases as more dilute cells are measured. 
Assuming that solvation does exist in these solvents, then, ac- 
cording to the law of mass action, the amount of solvation per 
mole of solute will be greatest in the most dilute solutions. 
However, on account of the greater concentration of the salt, 
more of the active solvent will be rendered inactive in the higher 
concentrations. The concentration of the ions and molecules, 
measured on the basis of active solvent present, will be abnor- 
mally increased in the concentrated solutions. Tfiie activity of 
the more concentrated solution in each cell will be relatively in- 
creased and this increase will become progressively larger as 
more concentrated cells are used. Hence, the activity ratio 
should and does increase with increasing concentration. 
It does not appear that the activity ratio will approach the 
concentration ratio at any attainable dilutions. In the calcula- 
tion of the concentration ratio by the conductivity method, the 
assumption is made that the mobilities of the ions are the same 
at all concentrations, including infinite dilution. That this as- 
sumption is sometimes erroneous is shown by the results herein 
reported. The discrepancy between the activity and concentra- 
tion ratios and between the observed and calculated electro- 
motive forces is in all probability due to variations in the mo- 
bility of the ions. 
There is, perhaps, another reason for this increase in the 
activity ratio with increase in the concentration of the salt. 
Walden 20 has found that the dielectric constant of salt solutions 
generally increases with increase in the concentration of the salt. 
According to the Nernst-Thompson rule this should mean a rela- 
tive increase in the ionizing power of the solvent, and hence in 
the number of the ions present. If this is true, we should ex- 
pect an increase in the activity of the ions in the more concen- 
trated solutions. As with solvation, so should this cause the 
activity ratio to become progressively larger with increasing 
concentration. 
20 Jour. Am. Chem. Soc., 35, 1649, 1913. 
