﻿234 Mr. Bernard Cavanaoh 



on 



components, whereas the " experimental '"' expression must 

 have the form 



t = M„|J + 2 ras (|t) ..... ( 3 ) 



the solvent appearing as one component only. 



Clearly 



(*±\ = (^±) + f S ^r_ .3^oi] , . (4) 

 \'dn s l m \dn,/n 0l L drc 01 ' dn s jM ' 



but the relation we have to use in making the change of 

 variables is that given by the condition for chemical equi- 

 librium among the molecules of the solvent, viz. : — 



rs|* .dHoii =o, (5) 



L On 01 J Mo 



so that 



\dn s J Mo \bn s / noi 



(6) 



and comparing then (2) and (3), 



BM;" Scol d^' (7) 



which could be regarded as physically obvious, as was done 

 in the preliminary treatment (previous paper). 



We shall abbreviate (1) by writing m for = — ; C for %c s , 

 and M G' for the " general " terms> so that, 



t = 2»o 1 (*oi-Rlog I ^| D ) 



+2» s (<#, s -Rlog I ^| u )+M G'. . (8) 



It will be convenient also to write G / for ^ — (M GT), 



the "general ' terms in s~^ ; similarly GJ for those in 



|i, etc. 

 dn s 



Now, in the first place, we have to show that it is permis- 

 sible to assume that (8) has already been so arranged that 

 Gr', G s \ Goi', etc., all vanish in the limit when C becomes 



