THE COLLOID-CHEMISTRY OF SOAPS 



71 



SOAP IN WATER 



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substances, like A 

 and B, (water and 

 soap, or alcohol and 

 soap) are mixed to- 

 gether. When B (or 

 the soap) is readily 

 soluble in A and the 

 concentration is right- 

 ly chosen, there rosu 1 1 s 

 a true solution at th<> 

 higher temperature. 

 This matter is repre- 

 sented by the region 

 marked A in the dia- 

 grams (the soap is 

 dispersed molecularly 

 or ionicaily in the 

 solvent). The lower- 

 most members of the 

 fatty acid series form 

 systems of this type 

 only, even at relative- 

 ly low temperatures, 

 but the members 

 higher in the aeries 

 form such systems 

 only at the higher 

 temperatures, 

 soap manufacturer 

 who makes his prod- 

 n.-t l.y "boil 

 in essence makes his 



: in such true 



What happens now 

 when the temperature 

 is lowered? The solu- 

 bility of the soap in 

 the water is obvious- 

 ly decreased. As the 



