82 



WORK OF J. N. PEARCE. 



A comparison of figs. 22, 24, and 30 shows that the hydrating powers of hydro- 

 chloric and sulphuric acids are of approximately the same order of magnitude, while 

 that of nitric acid is slightly less. 



Figs. 23, 25, and 31, representing the total amounts of combined water for the 

 three acids, show that the same relation holds here as for the hydrates. 



Table 63. Sulphuric Acid Data for Freezing-point and Conductivity Measurements, 



Specific Gravity, and Hydrates. 



DISCUSSION. 



Fifteen salts and three strong acids have been studied in this investigation. We 

 have worked with solutions covering a range of concentration from 0.01 to 3.0 nor- 

 mal; at one extremity are found to predominate, in a very pronounced manner, those 

 influences due to the ions; at the other, those due to the molecules also manifest them- 

 selves. In this way we have attempted to compare the relative effects of the ions 

 and the molecules upon the molecular lowering of the freezing-point and the dis- 

 sociation. 



Comparing, first of all, the freezing-point lowerings for any given solution, it is 

 found that, without exception, the molecular lowering calculated from the dissocia- 

 tion decreases regularly with increasing concentration. Naturally, this follows from 

 the fact that the decrease in dissociation is regular throughout. On the other hand, 

 the corrected observed freezing-point lowering decreases very rapidly in the dilute 



