ON THE ^-ELOCITY OF CHEMICAL REACTIONS 



25 



According to Gouldberg and Waage's law the rate at which the 

 cane sugar disappears should be proportional to the amount left in 



the solution. Hence 





kz. 



Or integrating between t^ and t 



Or 



^ {i-tx) =log,^=2-3026 log, 0^ 

 2-3026, 



The third column in the table contains the values of 



fc 



2-3026 



calcu- 



lated by this formula, using the value ^,=15 minutes so as to avoid 

 extrapolation. It appears that ^' as calculated above is not a constant. 



L^ 



Fig. 4. 



The decrease in its value indicates that the velocity of the reaction is 

 greater at the beginning or less at the end than would be expected 

 from Gouldberg and Waage's law. During the reaction, of course, 

 the amount of water present changes perceptibly, but not enough to 

 account for the large variation of k. The total change during the 

 entire reaction is less than 2 per cent. The deviation from Gould- 

 berg and "Waage's law may be due to the relatively large quantity of 

 hydrochloric acid in the solution. To decide whether it is or not 

 will be the object of further investigation. 



The second method is based upon the change in the volume of 

 the chemical system during the reaction. In order to measure the 



