Conductivity of Organic Acids in Ethyl Alcohol. 123 



Assuming that a given acid in alcoholic solution obeys the dilution law, 

 if we increase the volume from v to v\, we have, instead of (I) and (II) 



and 



& = v,k ( (IF) 



Combining (II) and (II 7 ) we get 



Likewise, from (I) and (I') there results 



2 



Since ^ >y, M,I> M and therefore Moo ~ Mcl > 1, it follows that & is 



77 



always less than and approaches this value as a limit. Therefore, as 

 molecular conductivity increases in concentrated solutions, as long as 



2 



the compound is slightly dissociated, the values of ^f found experimen- 



M 



9) 



tally will not differ greatly from - ; but, with increasing dilution and 



2 



greater degree of dissociation, ^-f will decrease in value and differ more 



M 



and more from - 

 v. 



As a result of his conductivity measurements on di- and trichloracetic 

 and /3-resorcylic acids, Wildermann drew the following conclusions : 



" (1) For dichloracetic acid, when v< 10 liters the values of are less 



jUe 



than A /^l; above 10 liters is greater than A / ; at dilutions from 800 

 > fj., \ v 



to 2,000 liters becomes almost equal to . The increase of is, 



M v n* 



therefore, continuous, not only in concentrated solutions, but also in 



the more dilute, to which the equation 2 = k should apply." 



M 



"(2) The same conclusions are even more nearly true in the case of 



j3-resorcylic acid, where the increase of is almost proportional to the 



M 



volume." 



!Zeit. phys. Chem., 2, 270 (1888). 



