492 



Dr. Harry C. Jone 



s on 



the 



slightly less than the constant 1*89, but the difference is so 

 slight that it is doubtless without important significance. 



Succinic Acid. — This acid, like the other dibasic organic 

 acids, dissociates into two ions, and the amount of dissociation 

 is considerably greater than that of acetic acid. The results 

 with succinic acid do not run as smoothly as could be desired, 

 and without knowing the cause for this I am inclined to 

 regard them as less exact than the other results. 



Comparison with the Conductivity Results of Ostwald. 



Ostwald has determined the conductivity of a large number 

 of organic acids, as is well known, and among them are 

 acetic and succinic acid*. The dissociation of these acids, 

 as calculated from his conductivity results and from mine on 

 the lowering of the freezing-point, are given below : — 



Acetic Acid. 



Concentration 

 gr.-mol. normal. 



Ostwald 's results from 

 Conductivity. 



My results from 

 Low. Freezing-point. 



0004 



per cent. 

 6-47 



per cent. 



8-5 



0-02 



292 



6-4 



o-i 



1-30 



1-9 



Succinic Acid. 



Concentration 

 gr.-mol. normal. 



Ostwald's results from 

 Conductivity. 



My results from 

 Low. Freezing-point. 



0-004 

 0-02 



o-i 



per cent. 

 12-08 



5-53 



2-72 



per cent. 



17-7 



15-6 

 6-3 



Ostwald's results are obtained by interpolation. The figure 

 for 0'1 succinic acid by exterpolation. The agreement be- 

 tween the two series of results is fairly good for acetic acid, 

 but for succinic acid my results are considerably higher. 



Ostwald, Zeits. phys. Chem. iii. pp. 174 and 272. 



