WORK OF C. M. STINE. 



33 



In order to compare the difference in the amount of water present as solvent in the 

 single solution and in the mixture with the difference in the value of M in the two 

 cases, these values are tabulated. (Table 19.) D HiQ is the difference in the amount 

 of water present as solvent in the separate solution and in the mixture. It is found for 

 a given salt by adding to the number of grams of water eliminated as water of hydra- 

 tion by the other salts in the mixture, the difference between the correction to weight- 

 normal standard in the case of the separate solution of the salt in question and in the 

 mixture. D m is the difference between the value of M in the single solution and 

 in the mixture. These values are plotted as curves in figs. 5 and 6. The concen- 

 trations are the abscissae, and for curve I the grams of water are taken as ordinates. 

 In curve II gram-molecules of water form the ordinates. 



Fig. 5. 





I. Difference between Water Present as Solvent o 



in Single Solution of Calcium Chloride and g 



in Mixture of Calcium Chloride and Stron- g 



tium Chloride. ( ~' 



II. Difference between the Values of M for Cal- 

 cium Chloride in Single Solution and in the 

 Mixture of Calcium Chloride and Strontium 

 Chloride. 



350- 



300 - 



200 







Fig. 6. 



I. Difference between Water Present as Solvent 

 in Single Solution of Strontium Chloride and 

 in Mixture of Calcium Chloride and Stron- 

 tium Chloride. 



II. Difference between the Values of M for Stron- 

 tium Chloride in Single Solution and in the 

 Mixture of Calcium Chloride and Strontium 

 Chloride. 



.5 1. 



Gram Molecules of Salt per Liter of Solution 



It is readily seen from a comparison of the curves that the decrease in the amount 

 of water present as solvent in the mixture is not accompanied by a corresponding 

 decrease in the values of M. Here again, as in the case of the mixture of calcium 

 chloride and potassium chloride, the difference in the values of M is nearly constant, 

 because the concentration of both salts present in the mixture is increased at the 

 same rate. Slight changes might be manifest if the ions and molecules have different 



