632 Mr. Bernard Cavanagh on 



This means that the thermodynamic behaviour o£ all the 

 ions in the same solution of (entirely univalent) ions is 

 the same and depends only on the total equivalent concen- 

 tration 0,-. 



Now this is precisely what has been deduced in recent 

 years as a purely empirical rule by Lewis, Loomis, Harned, 

 Ming Chow, and others *. 



It is a very significant fact that these workers have shown 

 this rule to hold quite closely at concentrations much higher 

 than are contemplated in the above. Thus, probably we 

 shall be close to the truth in regarding %Xrcf){r) as a function 

 of Cj, even at these somewhat higher concentrations where 

 it does not take the simple form Ru'C$. 



For tentative preliminary treatment of the higher con- 

 centrations, the use of the general form 



R2ui'Cr i+1 (96) 



mayjbe suggested, being fairly elastic since m-i, ??i 2 , can 



have any positive values, and possessing the advantage of 

 being easy to work with since it gives 



U = M ^ + 2n lWl -BM c :WCr i+1 , (97) 



ir = M (6 M -r 2RC0 + Imfa-n log Cl ) -EMo^'Cr^ 1 , 



... (98) 



^^M+Ra^+Sm^'Cr}, . . . (99) 



|* =*. -Rllog^ + S^^^/C^}. (100) 



That is 



i = 2 + 2m 1 cj> 1 , Gr\ (101) 



log^'^^'Cr. • • • • (102) 



On the basis of Milner's calculation the first m would 

 be J, and the rest higher than J, so that (94) and (95) 

 would be the limits of (101) and (102), as found by Lewis 

 and Linhart. 



For bivalent binary electrolytes one would expect the 

 same form of virial with a different limiting parameter B. 



* Journ. Airier. Chem. Soc. xxxi. p. 335 (1909) ; xxxviii. p. 1986 

 (1916). xxxviii. p. 2356 (1916) ; xxxix. p. 1138 (1917). xxxvi. 

 p. 632 (1911) ; xlii. p. 488 (1920). xxxvii. p. 2460 (1915X 



