290 



ill case a is {dP)^ <[ 

 „ „ f> „ (dP). < 

 „ ,. c „ {dP), ^ 



as is indicated also in fig. 2. 



In fig. 1 the pressure niaj as well increase as decrease in the 

 case (i; it is apparent from (31) that {dP)x shall be positieve for 

 large values of .r, :.r,. As L, (and consequently also g,) is the liquid 

 wliicli contains the most of the solid substance F we shall call Z, 

 (and consequently' also (/,) the concentrated and L^ thé diluted solution. 



We, therefore, find the following: 



when the tlireephases-triangle 8olid-li(|Mid-li(|iiid turns its concen- 

 trated solution lowai'ds the side of the components-triangle (fig. 1) 

 then the temperatui'e increases and the pressure generally decreases; 

 only when the concentration of the new substance in the diluted 

 liquid (consequently x^) is much larger than in the concentrated 

 liquid consequently .i-,), then in the case a the pressure may incre- 

 ase also. 



In (ig. 2 in the case c the pressure may as well increase as 

 decrease; it ap|)ears from (33) that {dP)^ shall be positive for small 

 values of x^ -.x^. 



Consequently we find the following: 



when the tlireephases-triangle solid-li(|uid-li(|uid turns its concen- 

 trated solution away from the side of the c(»mponents-tiiangle (fig. 2) 

 then the temperature decreases and generally the pressure also. 



Only when the concentration of the new substance is much larger 

 in the concentrated solution {.i\) than in the diluted solution f.r,), 

 then in the case c the pressure may also increase. 



We may obtain the previous results also by using the P, T'-dia- 

 gram of the equilibrium E{x:=Q). We may deduce this in the 

 following way. 



The direction of temperature of the equilibrium [G) = F -\- L^ -\- L^ 

 is defined by the sign of the coefficient of the phase f^r' in the isovo- 

 lumetrical reaction (19). As é A T^ may be as well positive as negative, 

 curve (G) may go, starting from the invariant point /, as well 

 towards higher as towards lower temperatures. 



The direction of pressure of the equilibrium [G) is defined by 

 the sign of the coefficient of G in the isentropical reaction (20). As 

 — b i\H is negative in each of the cases a, b and c, curve {G) 

 proceeds, starting from the invariant point i, towards higher pressures. 



As further, in accordance with (17): 



