Rkflly and HicKiNBonoM — Distillation of Volatile Fattij Acids. 129 



Expeiimeiits were cai-ried out, adding 50 c.c. of a normal solution of sodium 

 acetate to 100 c.c. of acetic acid, the determination of tlie distillation constant 

 being made in the usual manner. To compensate for the increased boiling- 

 point of the solution, the constant was determined in presence Of other salts 

 of the same molecular concentration. 



The results are given in Table VI, and the percentage increase is given. 

 The results cannot be explained simply. It is noteworthy that sodium 

 acetate causes only a slight increase in the constant compared with other 

 salts, while the presence of copper sulphate actually reduces the distillation 

 constant. Further, the retarding influence of copper sulphate is shown when 

 a dilute butyric acid solution (containing copper sulphate) is distilled. No 

 other salt among those examined appears to have a similar effect at the 

 dilution employed, although several other substances were studied, it is 

 possible that in some cases, i e., copper sulphate, in addition to a physical 

 alteration in the solution, there may also be some chemical change. 



It appears that the alteratioi 



salts, except copper sulphate. S: 



in the ionisation of the acid cannot 



account for the results, for sodium acetate has less effect than any of the other 



milarly an increase in the boiling-point 



of the solution does not explain the variation in the constants. 



[Summary. 



