﻿Molecular Thermodynamics. 243 



anomaly is that in a "complex'' solvent the process of 

 dilution is not quite so simple as in a "simple" solvent, 

 being accompanied by a change in the constitution of the 

 solvent — a reversion, in fact, to the constitution of the pure 

 solvent. It is, of course, plain that M 2<7 01 Ac 01 , or SgfoAwoij 

 is the ("chemical") heat evolution accompanying this 

 reversion (at constant temperature and pressure). 

 With (44) analogously we have 



U = M m m -» Xn s u s + M ti( Ac 0U . . . (46) 



V = M vm + Ws + M XiWW, • • • (47) 



and it may easily be verified from (LI) that 





(48) 



Appendix to Section III. 



A simple example, which is essentially merely illustrative, 

 but may possibly be something more, will serve to make clear 

 the practical significance of equation (26) concerning the 

 slight modification of the " general JJ terms. 



In section V. of the first of these papers was obtained for 

 the general term in the case of a dilute solution of a binary 

 strong electrolyte 



M G'=RM <£V /2 , (49) 



where (// depended, in some way, upon a certain " effective" 

 dielectric constant (D), which, at sufficient dilution, would 

 be that of the pure solvent. 



Let us suppose that D depends on c s in such a way that <f>' 

 is a linear function of c s 



4>'=4>o'(l + ac,) 9 (50) 



and also, in the first instance, that this effect of c s on D is 

 entirely independent of its effect on the constitution of the 

 solvent, that is, that the slight change in the latter produced 

 by the addition of the electrolyte would alone [if produced, 

 for instance, by some different solute, c„ the concentration 



R 2 



