44 On Oxalic Acid. 



Two hundred grains of pure crystallized sugar being 

 treated with diluted nitric acid in the usual way, yielded 200 

 cubic inches of carbonic acid, 64 cubic inches of nitrous gas, 

 and 70 cubic inches of azotic gas. But these numbers, 

 though the result of a good many experiments, are not to be 

 considered as very exact. The uncertainty depends upon the 

 property which the solution has of producing more gas after 

 the sugar is decomposed, at the expense of the oxalic acid 

 formed. Now, it is difficult to stop at the precise point. 



The whole weight of oxalic acid, which can be obtained 

 from 200 grains of sugar, amounts to 116 grains. If the 

 experiment be properly conducted, the whole of the sugar 

 is decomposed, or at least the quantity of residuary matter 

 is small. 



From the preceding statement, there is reason to conclude 

 that 100 grains of sugar, when decomposed by nitric acid, 

 yield, 



Grains. 



1. Oxalic acid crystals 58 grains, or real acid 45 



2. Carbonic acid 100 cubic inches, equivalent to 46'5 

 while these are evolved obviously by the decomposition of 

 the nitric acid. 



1. Azotic gas 35 cubic inches equivalent to 10*62 



2. Nitrous gas 32 cubic inches equivalent to 10*85 

 Now, as nitric acid contains no carbon, it is obvious that 



the oxalic acid formed, and the carbonic acid evolved, must 

 contain the whole carbon contained in 100 grains of sugar . 



Grains. 



45 grains of oxalic acid contain of carbon 14*40 

 46*5 grains of carbonic acid contain of ditto 13*02 



Total 27*42 



therefore 100 grains of sugar contain 27| grains of carbon* 

 The azotic gas and nitrous gas must have been originally 

 in the state of nitric acid, and must have given out oxygen 

 when they were evolved. But nitric acid is composed of. 



Oxygen. 

 Azote - 10*62 + 25 

 Nitrous gas 10*85 + 4*5 



2Q-5 



Therefore 



