287 



F + (i/,,r^(l + a) L, LHLV . . . . (17> 



(i- + b)L,:^F + bG A //'AF' ... (18) 



Herein is : 



LH — {1 + «) H, — H — aH, A- H' = n + bil, _ (1 + fc) H, 



A r= (1 + a) r, — F- aV, A F' = r + 6 f, — (1 -+ b) F, 



In (17) and (18) a ami 6 may be as well positive as negative. 

 It follows from (17) and (18) for tlie isovolnmetrical reaction: 



(A F+ A F') F — (1 +«) A F' L, + [aA V' — {I i b) LV] L, + bAV. G= 

 A //A F' -A//'. A F (19) 



and for the isentropical reaction : 



— {LH^LH')F^(\^a)LH'.L,— \aLH'—(\-\-b)LH]L,-bLn.G=0 

 AH LV — AH' AV . ..... (20) 



We now add to this eqnilibrinm E {.v ^^ 0) a new substance A', 

 which occurs in the two liquids L, and L, only. With the aid of 

 (19) and (20) it then follows from (7) and (8): 



.¥.(d2')^= — (1+a) AF'. «, + [aAF' — (1-1-6) AF].(,-, . (21) 

 M.(dP),= -{\ ^a)AH'..v, -\-[aAH'-{l+b)AH]x, . (22) 

 wherein : 



M = (AH.A F' — A /ƒ'. A V):R T 



It follows from (21 1 and (22): when we add to the equilibrium 

 E [.V — 0) a new siibslauce which occurs only in the two liquids, 

 then the temperature as well as the pressure may be increased or 

 decreased. 



We now shall assume that the four phases are situated with 

 respect to one another, as on the line Y Z m fig. 1. Then we have: 



,'/>y, > '/, >,'/,. 



It follows from (17) and (18) for the determination of a and b: 

 ^/ + «.'/, = (1 f «) .'/, (1 + b) .V, = V + by, 



a = z=: (2o) 



Vx-y, y^—Vi 



so that a and b are positive. Further we assume that i'"'and L, and 

 also that L, and L, are not situated very close to one another, so 

 that a is neither very small nor very large. When F and L, and 

 also L, and G are not situated very close to one another, then also 

 b is not very small and not very large. 



As now A V' is positive and very large with respect to A V, M 

 is positive. 



Further we may distinguish the following cases. 



