Properties of Liquid Mixtures. 55 



throughout ; still the experiments show it to he a remarkably 

 good empirical rule for mixtures which do not contain a very 

 small proportion of either component, extending in the c;ise of 

 carbon tetrachloride-benzene mixtures from 8 to 91 per cent. 



Fig:. 4. 











y 











a/ 



/ * 









V 



4 



^ 





*^ 













♦ ' 













log q 



0-5 



The empirical linear relations are then : — 



For carbon tetrachloride-benzene ...log £ = 0065 + 0947 log<7, 

 „ carbon tetrachloride-toluene . . .log t = 0*440 + 1/0 log q. 



These relations are intended as a solution of the differential 

 equation (11) in the foregoing paper. Margules proposes 

 a more complicated solution, which satisfies the condition that 

 for dilute solutions the lowering of the vapour-pressure of the 

 other component (the solvent) should be normal, i. e. according 

 to van 't HofF and Raoult's rule. It is doubtless possible to 

 represent the experimental results that way by using a 

 sufficient number of arbitrary constants ; but I have not 

 thought it worth while to do so, as it is complicated, and 

 seems to go rather beyond what the experimental data justify. 



