METHOD OF DETERMINING SOLUBILITY 



31 



AN IMPROVED METHOD OF DETERMINING 

 SOLUBILITY. 



W. S. HENDRIXSON. 



In the continuation of work on acid sodium and acid potassium 

 phthalates as standards in acidimetry and alkalimetry 1 , it seemed 

 desirable to study among other properties, the solubility of these 

 salts. 



It seems to be generally recognized that none of the methods 

 for determining solubility is wholly satisfactory. Among the 

 major difficulties are these: The somewhat complicated machin- 

 ery necessary to agitate the liquid in the thermostat, and the 

 solvent, and the difficulty of securing a specimen of the clear 

 solution for analysis, without change of temperature. fSince this 

 laboratory-, like most others, is supplied with a practically un- 



FlG. 1. 



limited amount of compressed air, the attempt has been made to 

 use it for the agitation of solvent and bath. To avoid the second 

 difficulty a special form of pipet has been used, which could be 

 wholly submerged during the time of agitation so as to be at the 



^roc. Icnva Acad. Sci., Vol. XXII, p. 217. 



