( 296 ) 



This Vtilite is pi-ohahlv loo liigii. For if we piil ' at al)oiit '2,1, 



then tv^. = 8,4 9, becuuse hk is by approximatioji about equal to 

 l),i z= 4o (o = tiie vohime proper of the molecules). Hence the limiting 

 volume /)„ for r^=h{=^ that of the complex molecules A,) is about 



— X8»'ic*=2,i o, because in most cases a value is foimd for this 

 4 ^ ^ 



limiting Nolume in the nei,uhl)ourhood of 74 *** '''^ critical volume. 



As now br^ =z r/j..=z4:0 and A„ =: Aj = 2,lc>, ^^o A/> = — A^ -j- 



-}- rA, = l,9o, and hence 



A6 1,9 



^ 4 



0.475. 



Z.// Lb Lh 



So we find for , supposing -- = -—: 



r — ft />A- /^/ 



Lh 



Lb l)k 0,475 



— 0.43. 



ri:-hk V,, _ ^ 2 1-1 



/'A- 



So the value 0.63, which we found above, is too high. l>ut we 

 must not attach too much importance to this circumstance, because 

 it is very well possible that ai lower temperatures and smaller 

 volumes, where association to molecule-complexes which are larger 

 on an average, will take place, and x accordingly assumes a higher 

 value, <f' will tutturallij decrease. We pointed out already above 

 that the quantity x is properly speaking, variable, and that we should 

 only consider it to be constant provisionally in the neighbourhood of 

 the critical point to simplify the considerations. 



Before we proceed, iiowever, and repeat the foregoing calculation 



for ^' = 2, we shall first calculate the relation - with the values 



bh 



found for m and n, and also the factors of - — and — ^ resp. m 



the expressions for RTkUnd /fi- We have viz. according to (6): 

 vf, 3w/ 3 X (1,107)^ 3,678 



j^ 3m=— 2n «7 — 2X0,969 1,740 



= 2,114. 



So we see that the ordinary theory of association, though /i differs 

 only little from 1, and in consequence in and n only deviate little 

 from 1, is perfectly adequate to account for the very considerable 

 diminution of the ratio v/c:bk from 3 to about 2,1, a value which 

 is in perfect harmony with the value computed by different investi- 



