CHAPTER IV 



The State of Dissociation of Acids and Bases During Actual 



Salt Formation 



summary of contents 



Not all salts are to be included with the strong, always totally dis- 

 sociated electrolytes. In the presence of undissociated salt molecules 

 there arise in the above developed dissociation laws complications which 

 are discussed below. 



38. Hitherto we based our considerations on the assumption 

 that of all electrolytes only the weak acids and bases are incompletely 

 dissociated, while all other electrolytes are completely dissociated. 

 Doubtlessly this assumption of complete dissociation is but one of 

 approximation which for such electrolytes as KCl must be practically 

 quite exact. But there are also undissociated salt molecules. We 

 are not as yet very well informed concerning them, but nevertheless 

 the following facts are known: 



In the first place it cannot be asserted in the case of solutions of 

 organic salts in organic solvents that these salts are completely dis- 

 sociated, which point will be taken up in greater detail in a later 

 chapter. Secondly, we are not justified in ascribing, without further 

 quahfication, the properties of salts of the strong or moderately weak 

 acids and bases to the salts of very weak acids and bases. If equiva- 

 lent amounts of acetic acid and aniline are mixed in an aqueous 

 solution, then this solution of aniline acetate differs from a KCl 

 solution insofar as here a far reaching hydrolysis occurs. Secondly, 

 we cannot, in this case, as we would with a KCl solution, deny the 

 existence of the undissociated salt, aniline acetate. Many electrolyte 

 effects would become more comprehensible, if such "actual" salt- 

 formation were assumed. It appears to the author that, for example, 

 the explanation of electrolyte effect on protein solutions is not very 

 adequate without the assumption of the formation of "actual" 

 protein salts. Just which of the ionic species tend to form undis- 

 sociated molecules cannot yet be accurately stated. It is only 



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