ON THE BOILING POINTS OF AQUEOUS SOLUTIONS OF ELECTROLYTES. 237 



have been able to strike off frequently approximately the same hydration value. It 

 need only further be mentioned that Garrard and Oppermann consider their error 

 limit large. 



The following two diagrams were drawn to show (l) the relation between the 

 number of grammes of associated water and the elevation of the boiling point in 

 decrees Centigrade, (2) the relation between grammes of associated water and the 

 gramme equivalents per litre. 



s 



I 



vS 



I 

 1 



*3 



2 3 4 5 6 



ORMS. ASSOCIATED SOLVENT 



Fig. 17. 



In the first instance approximately linear relations are seen to exist throughout ranges 

 of boiling-point elevation of from 3 to 6 degrees Centigrade. In the latter case the 

 curves are concave towards the gramme equivalent axis, the curves being approximately 

 straight lines until a concentration of from three to four or five gramme equivalents is 

 reached ; which means that the rate of increase of hydration is fairly maintained up 

 to these concentrations, but that a point is reached for the salts whose data have been 

 plotted when the rate of increase of hydration with increase of concentration is not 

 fully maintained. 



