18 ART. 10. — K. IKEDA : STUDIES ON THE 



which becomes by (5) 



1 dn^ _ 1 (???2 1 df}^ 



This can be readily integrated to 



1 7 7?i 1 ; ??., 1 7 n., t . 



p/"Är = T/"ivr = T/"i^ (") 



We have also the relation 



T= 'h Pj + 'h 7^,+ '-< F., (?>) 



These three equations of (ft) and (Z») are sufficient to determine 

 the values of ?2i, n^^ and n?,. 



(c) 77(6 Boiling Point of an Ideal Solution. 



As explained under (a) the relation between the total pressure 

 on one hand and the vapour pressures of the j^ure components 

 and composition on the other is very simple at a constant tem- 

 perature. Hence if the vapour pressure of the components be 

 given as a function of temperature, the relation between boiling 

 point and composition can be readily ascertained. Now let the 

 vapour pressure of the components be expressed by : 



F, = <p,{T\ F, = cr,{T), etc. 



and let ^ be the constant pressure under w'hich the solution 

 boils, then we have 



lh + Ih+ ^f\<f,{T)+a<r,(T)+ = %i (9) 



The variation of the vapour pressure of each component with the 

 temperature is given by the equation of Clapeyron-Clausius : 



"^ In Pi 5i_ 8 In P., __ (/■> 



or - PT-' dT PtT-' 



