THEORIES RELATING TO ELECTROLYTIC SOLUTIONS 347 



Lorenz 30 has tested the applicability of Hertz's function to aqueous 

 solutions of binary electrolytes and has concluded that this function is 

 applicable. As has just been pointed out, this was to have been expected. 

 It should be noted, however, that the value of A, according to Lorenz, 

 differs appreciably for different electrolytes. This result may, in part, 

 be due to the fact that the function has been applied at concentrations 

 where the viscosity effects become appreciable. 



It is evident that Hertz's function will not be generally applicable 

 to solutions in non-aqueous solvents, certainly not unless the value of 

 A is assumed to differ largely for different electrolytes. Furthermore, it 

 will be entirely inapplicable to solutions in non-aqueous solvents of low 

 dielectric constant at higher concentrations. It is evident from Equation 

 126 that the factor of u 3 is essentially positive so that A A must 

 necessarily increase with increasing concentration. It is known, however, 

 that, in solvents of low dielectric constant, the value of A passes through 

 a minimum, after which the value of A A decreases with increasing 

 concentration. This theory, like others of its kind, is at best restricted 

 in its applicability. As yet it has not been compared with experimental 

 data in a sufficient number of solutions to make it possible to form a 

 clear opinion as to the range of its applicability. In any case, it is in- 

 applicable to solutions in solvents of very low dielectric constant, even 

 though these solutions may be dilute. Here again, as in the case of 

 Milner's theory, the difference in the behavior of strong and weak elec- 

 trolytes remains to be accounted for. 



4. Miscellaneous Theories. A great many other theories have been 

 suggested to account for the behavior of electrolytic solutions. In gen- 

 eral, these theories have not been worked out sufficiently to comprehend 

 within their scope more than a limited number of properties of a limited 

 number of systems. Many of them, indeed, are purely qualitative in 

 character. 



To account for the increase in the conductance of solutions of elec- 

 trolytes in solvents of very low dielectric constant, Steele, Macintosh 

 and Archibald 31 have suggested that at higher concentrations the elec- 

 trolyte polymerizes, and that only these polymerized molecules are capa- 

 ble of ionization. They show that, if a sufficient degree of polymerization 

 is assumed, an ionization curve is obtained somewhat similar in form to 

 that of ordinary electrolytes in aqueous solution. Thus far, this theory 

 is purely qualitative in character and an exact test of its applicability 

 is therefore not possible. We should expect, however, that if only 



10 Lorenz and Michael, Ztschr. /. anorg. Chem. 116. 161 (1921): Lorenz and Neu. 

 ibid., 116, 45 (1921) ; Lorenz and Osswald, ibid., 114, 209 (1920). 



"Steele, Macintosh and Archibald, Phil. Trans. [A] 205, 99 (1905). 



