öö ART. 10. K. IKEDA : STUDIES ON THE 



CHAPTER II. 



Quasi-ideal Solutions with one Associated Component. 



Ill the systems, which we have been considering in the 

 preceding chapter, it has been assumed that chemical changes 

 do not take place in the homogeneous phases ; because if the 

 state of isomeric or polymeric equilibrium of the independent 

 components be disturbed on mixing them, or if they enter into 

 combination with one another, energy- and volume-change must 

 necessarily occur and conditions (1) and (2) will not be satisfied. 

 Yet, that the chemical species^^ could be mixed without such 

 changes is not excluded, provided the chemical reactions were 

 checked. In order to make the matter more readily conceivable 

 we may suppose with Luther (Zeits. Electrochem., I2, 87 ; 

 1906) that a negative catalyser has been added to the chemical 

 species before mixing. This does not of course affect the chemical 

 potentials. Hence if the chemical species are miscible without 

 volume- and energy-change, the chemical potentials have the 

 values given by equation (3). Such a solution, in which re- 

 versible chemical reactions take place but whose volume and 

 energy are equal to the sums of the respective quantities of the 

 component chemical species, we propose to call a quasi-ideal 

 solution. It can be readily imagined that actual solutions which 

 approximate more or less closely to the quasi-ideal solution will 

 be far more numerous than those which approximate to the ideal 



1) The term " chemical species," wlaich has been employed by some older writers but 

 has lately almost gone out of use, may be employed to denote distinct clicmical entities real 

 ur imaginary. It is preferable to the term " molecular species." 



