Tlte Oxidation of Cane Sugar. 



121 



According to the equation each molecule of sugar should 

 require twenty-four atoms of oxygen for its complete oxidation 

 toCOo. 



Results of Experiments. 



N N 



Comparatively strong solutions containing — KMnO^ and — 



sugar with large excess of H0SO4 (100 molecules of KMn04 being 

 present to 1, 2, 4 and 6 molecules of sugar in different experi- 

 ments) were left stand over night. 



The results obtained were complicated and in every case far 

 too much KMnO^ was reduced. This was evidently the result 

 of some secondary action, probably the reduction of KMn04 by 

 the MnO,. 



Consequently I decided to restrict myself to the use of dilute 

 N. 

 50^ 

 N 

 ^^ sugar (containing '6843 grams per litre). 



(i.) Experiments at ordinary temperature (21°C.). 



Solutions were made up as indicated in table on Friday after- 

 noon and allowed to stand until the following Monday morning, 

 i.e., 64-68 hours. The solutions were then diluted to lOOccs. and 

 sufficient filtex^ed into a burette to titrate against either 10 or 



20ccs. ^ [Fe.l 

 oO "- -' 



The results shew that the reaction is not complete after three 



days' contact at this temperature. 



Table I. 



Time of experiment, 64-6Shrs. Temperature 21°C. 



N N 



50CCS. — KMnO^ and Sccs.-H.SO^ were employed in each experiment. 



solutions, viz., ^KMnO^ (containing 3-1638 grams per litre) and 



