36 



bound glycerine ilian agrees with an immediate splitting up into 

 glycerine and three molecules of fatty acid. He could therefore 

 £\ssume analogous behaviour for the acetines. 



Jul. Meyer') has mathematically examined the course of the sapo- 

 nification in acid solution of esters of bivalent acids or alcohols, and 

 has brought this into e(|uation in a very lucid foiin. It is evident 

 from his formulae that when the first stage passes twice as quickly 

 as the second, the whole sa|)onification becomes seemingly mono- 

 moleculai". Measurements of velocity carried out by him for the acid 

 saponification of liie glycol acetates and of esters of different symme- 

 trically i)uilt bi-basic acids, confirm this fully. 



Also to J. Meyer's conclusions the objection might be made that 

 a simply monomolccular sa|)onification ex[)lains his residts equally 

 well. J. Meyer has, however, also determined the velocities of sapo- 

 nification of the methyl esters of the asymmetrical camphoric acid. 

 Of the dimethyl camphorate one ester group now appeared to be 

 much more quickly split off than another. Hence the velocity 

 constants in the saponification of di- and mono-ester are not in the 

 ratio of 2:1, so that here the results of the measurements of velocity 

 lead us to conclude dii-ectly to the process in stages of the reaction. 

 The assumj)tion that also in the saponification of glycol esters etc. 

 the reaction takes place in stages, is then perfectly justified. Besides 

 Jul. Meyer's experiments support Geitel's view that the acetines 

 in acid solution are saponified stagewise. 



The Saponification in Emulsion. 



§ 2. Both Geitei/s papers and those of Jul. Meyer treat the 

 saponification in solution. In the saponification of fat, however, 

 always more or less fine emulsions of fat and an aqueous solution 

 are woiked with, and it is, therefore, now the question in what 

 way the reaction lakes place in this case. 



\n the first place it is the (piestion : Where does the reaction take 

 place? There are, namely, three possibilities: 



1. Reaction takes place in the water phase. 



2. Reaction takes place in the fat phase. 



3. Reaction takes place on the boundary of the two phases. 

 Let us consider each of these possibilities separately. 



1 . The reaction takes place in the ivater phase. 

 In this case the velocity with which the triglyceride is converted, 

 is determined by the number of molecules dissolved in the water 

 1) Z. f. phys. Ghem. 66 81 (1909). 



