WORK OF H. R. KREIDER. 105 



was worked out. These facts indicate that there is a definite relation between these 

 two ratios. 



We have found minima in most of the curves for mixed solvents. 



We have tabulated the dissociation of several salts in methyl alcohol and ethyl 

 alcohol as determined by the boiling-point method. 



The following work is a continuation of that already discussed. 1 In our earlier 

 work we measured the conductivity of certain salts in very dilute solutions of ethyl 

 alcohol and methyl alcohol. The salts employed were potassium iodide, ammonium 

 bromide, potassium sulphocyanate, lithium nitrate, sodium iodide, calcium nitrate, 

 cobalt chloride, and copper chloride. The conductivities of these salts were measured 

 in solutions ranging in concentration from N/1600 to N/51200. The conductivities 

 of these salts in more concentrated solutions had been previously determined by 

 Jones and his coworkers. 



In our former work a well-defined maximum in conductivity with increasing 

 dilution was noted in solutions of a number of salts. Certain relations between these 

 maxima were pointed out. The ratio between fi^ for a certain salt in methyl alcohol 

 and fx^ for the same salt in ethyl alcohol was found to be a constant for different 

 binary salts. The f ollowing values were obtained for c = /jl x methyl alcohol//**, ethyl 

 alcohol. 



Binary Electrolytes: c c 



LiN0 3 at = 2.37 NH 4 Br at 25 = 2 . 44 



Nal at = 2. 37 Nal at 25 = 2. 17 



Ternary Electrolytes: 



CoCl 2 atO = 3.68 



The conductivities of other salts at the same high dilutions have now been meas- 

 ured, with the object of seeing whether the relations given above are general. The 

 salts used were sodium bromide, lithium bromide, and cobalt bromide. The work 

 with potassium sulphocyanate in methyl alcohol was repeated, and more satisfactory 

 results obtained. 



Most of the measurements were made at the dilution of complete dissociation. 

 The values of ju*, for the same salt in methyl and ethyl alcohols are then compared 

 with each other, and also with the value of fJL M for the same salt in water. The appa- 

 ratus employed is the same as that previously described, with some minor improve- 

 ments. The same cells, with concentric platinum cylinders as electrodes, were used. 

 One cell having the electrodes closer together and a smaller constant was also 

 employed. 



Both salts and solvents were purified with special care. A solution of a certain 

 concentration was then prepared as the mother-solution, and from it the other solu- 

 tions were made. Some of the solutions were as dilute as N/102400. 



The precautions observed were the same as those previously discussed. In addi- 

 tion, greater care was exercised in purifying the methyl alcohol. It is very difficult 

 to get methyl alcohol in large quantities in such a state of purity that its specific 

 conductivity is low enough to obtain good results for such dilute solutions. It was 



'Amcr. Chcm. Jour., 45, 282 (1911). 



