Art. XVI. — The Oxidation of Cane Sugar hy Aqueous 

 Solutionis of Potassium Permanganate. 



(With Plates XXI., XXII.) 



By W. HEBER green, B.Sc. 



(Acting-Demonstrator in Chemistry in the University of Melboiarne). 

 [Eead 8th December, 1898]. 



The Dictionnaire de Chemie states that sugar is oxidised 

 entirely to carbonic acid and water by permanganate of potash 

 in an acid solution. 



Watt's Dictionary says that sucrose is easily oxidised by all 

 ordinary oxidising agents and that KMn04 is sat'd to yield CO.^ 

 and H.^O ; but that Liebig and Pelouze had found that oxalic 

 acid was produced unless an excess of KMnO^ were present, in 

 which case carbonates were formed. 



But the accuracy of these statements has been called in 

 question, and at the suggestion of Professor Masson, this 

 research has been undertaken with the view of testing their 

 validity. 



It may be observed, however, that the action has not been 

 wholly overlooked, and those chemists who have investigated 

 the subject have found, speaking generally, that the sugar 

 molecule is broken up into molecules of smaller carbon content ; 

 oxalates, formates, carbonates and salts of other acids being 

 formed under varying conditions ; but considerable differences of 

 opinion prevail as to the manner in which the permanganate is 

 reduced. 



Literature of Sugar Oxidation. 



Maumene {Compt. Rend., 75, p. 85) gives this equation as the 

 result of his experiments : — 

 1 0Ci,H,,Oii + K.,0 -Mn^O^ = 



9Ci.,H,,0i,;K,0 + 20gHioO.,-K.,0 + minA + H,0 



(potassium hexepate) (potassium trigenate) 



