ELECTROLYTIC DISSOCIATION 



67 



As an example, the data for chloracetic acid at 14 are 

 as follows l , the calculated values of - - being derived from 



the equation 



M 2 

 7 ' r^r = " 



205 



408 



2O60 



4080 



IOIOO 



20700 



CO 



51-6 



132 

 170 



251 



274 



295 

 300 



311 



Clearly here the decomposition as measured electrically 

 follows the course anticipated on the theory of dissociation. 

 Accordingly we find, e. g. for dichloracetic acid, which also 

 follows Ostwald's law, that the values of t obtained from 

 the molecular depression of the freezing point (M), and 

 those from the conductivity, agree 2 . 



Normality 



0-002599 



0-005177 



0-01033 



0-01447 



0.02048 



0-02778 



1.966 

 1.911 

 1.852 

 1.763 

 1.717 

 1-69 



The agreement is satisfactory, and might well be complete 

 if we remember that the freezing-point measurement 

 always the more difficult refers to o, while the electrical 

 is for 1 8. 



Electrolytes which do not follow Ostwald's law of dilution. 

 The case is quite different for salts and strong acids and 



1 Van 't Hoff and Reicher, Zeitschr.f. Phys. Chem. 2. 781. 



2 Wildermann, 1. c. 19. 242. 



E 2 



