( l'JH ) 



Composition of the biuar.v mixture iu Critical mixiugtempcraturc 



Molec. Alcohol ou 100 Molec. after the addition of 



Alcohol + '.vater. succinonitrile. 



Point d 56= 



5.7 41°5 



12.1 30°5 



25.9 12° 



30.1 Point d' 7°5 



66.G Point e' 8°5 



70.4 11° 



84.6 21° 



100 Point e 3r5 



Of the doited line d' e' only a small part could be realized ; the 

 greater part it is however impossible to determine. Yet we are led 

 to suppose that the line d' e will run as drawn in the figure viz.: 

 with a minimum-temperature at ± 3° coinciding with the point in 

 which in fig. 1 the two connodal lines merge into each other. The 

 difficulty of determining the course of the curved line lies iu the 

 fact of the two liquid-phases presenting there less stable equilibriums ; 

 the few cases iu which Dr. Schreixkmakers succeeded in obtaining 

 them, were insufficient to deduct the critical mixingtemperatures 

 from. 



Besides the question of the critical mixingtemperatures of ter- 

 nary systems, we can set ourselves many other problems one of 

 which T shall discuss. 



Take a binary mixture viz. one of water and phenol ; the mixing 

 temperature of such a mixture depends upon its composition ; f.i. the 

 mixingtemperature of a mixture containing 10.9 pCt. of phenol is 

 =t 46°. This mixingtemperature is altered not only l)y pressure, 

 but also by the addition of a third component ; it may be raised or 

 depressed. An example of a rise Dr. Schreinemakrrs has determined 

 experimentally by taking as a third component aniline; he found 

 that the mixingtemperature began by rising from 46° to about 

 163°, to fall again after a further addition of .aniline. In order to 

 draw this line in fig. 3, only the components phenol and aniline 

 of the ternary mixture are considered. Owing to the proportion of 

 water and phenol being constant in all the mixtures, the entire 

 composition is known. "We have : 



