328 ILLINOIS STATE ACADEMY OP SCIENCE 



charcoals are caused by the adsorbed salts and gases 

 rather than by the charcoal. 



CANE SUGAR CHAECOAL 



To prove the theory some charcoal containing no me- 

 talic salts was prepared from pure cane sugar, and a two 

 gram sample tried with N/20 sodium hydroxide and ti- 

 trated with N/20 hydrochloric acid (curve represented 

 on plate VII). This shows no depression of the curve 

 at either end or adsorption of ions, but does show the 

 presence of acids, as the neutral point is reached with 

 about five cc. less acid than when no carbon is used. 

 However, after numerous successive washings with boil- 

 ing distilled water the curve was made to nearly follow 

 the normal curve. Although it was practically impos- 



13. 

 12. 



il 

 104 

 9' 

 8. 



7. 

 6' 



5 



4- 

 5 

 2 



14 ^ cc. A-cid 



L_i£ "-^ ^-° ^-5 ^P ZS ^ 



Plate VII. 



sible to remove all the adsorbed organic acids from the 

 charcoal by this method, the results of the successive 

 washings show that the change in curve was due to im- 

 purities rather than to the charcoal. 



To check the work of Bovie a sample of this sugar 

 charcoal was also titrated with solutions of N/100 acid 

 and alkali, and it was found that the sugar charcoal fol- 

 lows the normal curve of the acid and alkali. Samples 

 of the other so-called purified charcoals gave curves 

 very similar to that obtained by Bovie, 



