CHEMICAL THEOEY OF SOLUTIONS. PAET I. 



75 



It is quite clear that the chemical species ©i and ©2 are 

 symmetrically related to the other chemical species. If we put 



C,+ C, = C, 



we get quite the same equations as in the foregoing section, and 

 the relations found tliere must apply to the present case without 

 any alterations. 



Now let the empirical molar fraction of tlie associated 

 component be x, and those of the normal components, y and z ; 

 then w^e have 



X = 



y 



C'a+vC'ß _ C^+uC,^ 





l + {u~l)C\, 





and 



l + (y-l)6'ß 



.(57) 

 .(58) 

 .(59) 



These equations together 

 wâth (30) enable ns to deter- 

 mine Ca, C;i, C{, and Co as 

 functions of the empirical molar 

 fractions. As Cp must have a 

 constant value for d + Co = C 

 = constant, it follows from {ö^) 

 and (59) that ?/ + -^ = constant. 

 But this is equivalent to re = 

 constant. The surfaces of Cx 

 and C'ß must therefore have the 

 forms represented in Figs. 15 

 and 16. The locii of the points 



Fier. 15. 



