Ueilly and HiCKiNBOttOM — blstillation of Volatile Fatii/ Acids. 121 



for heating. The distillate was collected in weighed cylinders, provided with 

 stoppers, in approximately eqnal fractions of 10 grammes each. Throughout 

 this investigation standardized barium hydroxide solution, approximately 

 OT IST, was used in titrating the distillate, precautions being taken to 

 eliminate the effect of carbon dioxide. 



For the interpretation of the experimental results an expression was 

 calculated from Nernst's law of distribution. From this law the following 



equation holds : — 



dx, ka a - X 

 dv f) V - v 



where x = acid in vol. v of distillate, 



a = initial acid in vol. V in tiask, 

 a - X = acid in flask at any time in vol. V - v. 



Integrating ' a - x I'V- 



where ha 



^ = — > 

 P 



from which it follows that log a - log {a 

 21 



20 



c) = ,i[logF-log(F-^)l. 



1-9 



T8 



17 



J 1-6 



1-5 



1-4 



1-6 1-7 1-8 1-9 



log (volume in flask). 

 Fig. 1. 



20 



21 



2-2 



The values of log (acid in flask) have been plotted against the values of 

 log (volume in flask), fig. 1. The line joining the experimentally derived 



q2 



