OF AQUEOUS SOLUTIONS. BARNES. 115 



The observations of Reyher, Wagner and Kanitz were made 

 on somewhat stronger solutions than those for which the above 

 expressions might be expected to hold, but they were considered 

 as probably sufficiently dilute to warrant the expectation of an 

 approximate applicability of the expressions. 



Simple Solutions. 



For the determination of the ionization constants in expres- 

 sions (1) and (2), one must know the ionization coefficients for 

 the four solutions examined in the case of each salt by Reyher 

 and Wagrler. Unfortunately all the observations on the vis- 

 cosity of these salts were made at 25 C., while all the available 

 conductivity data, from which the ionization coefficients are 

 obtained, were at 18C., and thus it was necessary either to 

 reduce the viscosity values from 25 to 18 or the conductivity 

 values from 18 to 25. This latter reduction was carried out, 

 as data for the former were not available. This involved 

 much work ; because for the determination of the ionization 

 coefficients at 25, it was necessary to obtain both the specific 

 molecular conductivity at 25 and the specific molecular con- 

 ductivity at infinite dilution for 25. 



Determination of the Specific Molecular Conductivity at 



Infinite Dilution for %5C. 



The value of the specific molecular conductivity at infinite 

 dilution for 25 for each salt was obtained from 1 Kohlrausch's 

 value at 18 by aid of 2 De'guisne's data. These data were 

 employed in obtaining the specific molecular conductivity at 

 25 from the values at 18, for the three weakest solutions 

 given in 8 Kohlrausch's and De'guisne's tables ; and the ratio 



8 was then determined, where ^ 25 and fi J8 are the 



f*l 8 



specific molecular conductivity at 25 and 18 respectively. 



Table I gives the values thus obtained. The concentrations 

 are expressed in gramme-equivalents per litre, and the specific 

 molecular conductivities in terms of this unit and of 10~ 4 times 

 4 Kohlrausch's new unit of conductivity (ohm 1 cm. 1 ). 



1 Kohl. u. Holb., loc. cit., p. 200, tab. 8. 



1 Ibid., p. 195, tab. 7. 



3 Ibid., pp. 159, 160, tab. 2. 



Ibid., p. 1. 



