DISCUSSION OF THE RESULTS. 



135 



ISO 



100 



50 



(COOH} 2 , 



C Z H Z (OH) 2 (COOH), 



DISCUSSION OF THE RESULTS. 



Ninety-eight compounds have been studied in this investigation, and about 

 1,500 solutions. Most of the results obtained are given in the above tables, 

 and some of these have been plotted in curves. We shall now take up certain 

 of these results and examine them in some detail. 



The salts of lithium (tables 2 to 5) give comparatively large lowering of 

 the freezing-point of water for binary electrolytes, and, therefore, show 

 considerable hydration. This is in keeping with the relation between water 

 of crystallization and lowering of the freezing-point. Lithium salts crystal- 

 lize with water, while the salts of sodium and potassium, in general, do not. 



The freezing-point lowerings produced by salts of lithium are plotted as 

 curves in figs. 3, 4, 11, 14, 15, 16, 17, and 19. Conductivity results are plot- 

 ted in figs. 7, 8, and 20, refractivities in fig. 12, and hydrates in fig. 53. 



The total amount of water held in combination by the dissolved substance 

 increases with the concentration of the solution, from the most dilute to the most 

 concentrated solution studied. This relation, as we shall see. holds for all of 

 the substances that are capable of combining with water. It is, indeed, a 

 necessary consequence of the law of mass action. 



The composition of the hydrates, i. e., the amount <>] water combined with one 

 molecule of the dissolved substance or the ions fanned from it, increases with the 

 dilution of the solution. This relation also is a fairly general one for salts. 

 Certain irregularities appear, but these are probably to be attributed to the 

 accumulation of experimental errors. 



