236 Proceedings of the Royal Society of Victoria. 



I have attempted to apply the equations for mono-, di- and 

 tri-molecular changes to the results obtained at 84°'5C. ; as was 

 to be expected they did not agree, the curve being evidently 

 of a much higher degree and requiring a considerably more 

 complicated equation. 



The results obtained so far may, I think, be summarized as 

 under : — 



1. Cane sugar is completely oxidised to carbon dioxide and 



water by potassium permanganate in dilute and 

 acid solutions containing excess of the permanganate. 



2. The potassium permanganate is reduced, under these 



conditions, to a hydrated manganese peroxide. 



3. A secondary action which proceeds simultaneously is 



caused by this precipitated oxide acting " catalyti- 

 cally," and reducing more of the KMnO^ to MnO„ 

 with liberation of oxygen gas. 



4. These reactions may be represented by the following 



equations : — 



(i.) Ci,H,,On+16KMnO, + 8H,S04 = 



8K,80, + 1 6MnO,, + 1 2C0, + 1 1 H,0 



(ii.) 4KMnO, + A-MnO, + 2H,S0, = 



2K,S04+ (.T + 4)MnO, + 2H,0 + 30, 



5. The primary action indicates a method for the estima- 



tion of cane sugar in dilute aqueous solutions, bearing 

 in mind the restrictions discussed on p. 235. 



6. The velocity of both reactions increases notably, but not 



in a simple manner, with the concentration, 

 acidity and temperature of the solution. 



7. When excess of potassium permanganate is not em- 



ployed, then lower oxidation products of sugar, 



such as formates and possil)ly oxalates and glycol- 



lates, are formed, as well us carbon dioxide. 



These experiments have been carried out in the Chemical 



Laboratory of the University of Melbourne, and I desire great- 



fully to acknowledge my deep obligations to Professor Orme 



Masson for valuable encouragement and advice afibrded me in 



connection with this work. 



