313 



For liquids p may of course always be cancelled against the so 

 inucli greater molecular pressure ''/„2. 



We will just mention that the earlier — inaccurate — expressions 

 were : 



, (6, \/a,-b, [/a,y ^ (6, \/a—h, [/a,Y 



3. Volume contraction with normal components. 



We must now try to find an expression for Av, and (hen also 

 for Avj and Av,, in order to be able to substitute in (1) and (2), 

 and to form an opinion of the order of magnitude of the different 

 parts. As 



we have also: 



Lv = h — {n^h^ + M,6,) + (u — 6) — w, (u/ — h^) — n, (u/ — 6,). 

 Now b =z n^h^ -\- nj)^y hence after application of the equation of 

 state, there remains : 



_ [n, + «,) RT «, RT n, RT 



i.e. with neglect of p: 



Lv =RT 





or 



Av = 



RT 



(^1 + ^J (^1 "i" + ^2 ^j") «1 <^ — «I ^i" ««a— n^u," aa^ 



RT 



+ 



as V = {n^v^° -\- n,v/) -|- hv. In consequence of this, with a = 

 Av - ^ "^ f 2 Aw (v—Av) + {Lvy J = 



RT 



aa.a. 



(n^-f n,)(wiü/ + n,v,*) a^a^-{n^v^'' a, + «,v/ a^){7i,\/a^-\-n^[/a^y 



which, worked out with neglect of Av by the side of 2v, and 

 putting ?2i 4" w, = 1 at R7\ gives: 



* , 2RT\ 

 Av{ 1 — = 



