1904.] on Development of the Theory of Electrolytic Dissociation. 563 



are charged with electricity, as Faraday's law demands. Probably 

 this objection has hindered an earlier acceptance of a dissociated 

 state of the electrolytes, to which, for instance, Valson and Bartoli 

 inclined. 



The gaseous laws that are valid for dilute solutions, have made 

 the calculation of the degree of dissociation possible in a great 

 number of cases. The first application of that nature was made by 

 Ostwald, who showed that the dissociation equilibrium between the 

 ions and the non-dissociated part of a weak acid obeys very nearly 

 the gaseous laws. The same was afterwards demonstrated to be true 

 for weak bases by Bredig. The strongly dissociated electrolytes, 

 chiefly salts, exhibit even in dilute solutions (over 0*05 normal) 



Buturate 

 Sulphate 



Salii) ot ParcLruoaruiwte 

 Fig. 9. 



anomalies, that are not yet wholly explained. Professor Jahn, of 

 Berlin, is at work upon this most interesting question. 

 '-- The equilibrium between a greater number of electrolytes has 

 been investigated by myself, and found to be in good agreement with 

 the theoretical previsions. This section includes the questions on 

 the weakening of an acid by addition of its salts, and on the so-called 

 avidity of the different acids, that is, the proportion in which two 

 acids divide a base at partial neutralisation. Calculation gives very 

 nearly the numbers observed experimentally by Thomson and 

 Ostwald. For heterogeneous equilibria between electrolytes the 

 theory is worked out by van't Hoff and Nernst, who have in this 

 way elucidated the common method to precipitate salts used in 

 analytical chemistry. 



