278 Mr Bevan, A Method of following the Course 



Hence if k 2 is large compared with k 1} that is the rate of de- 

 composition of the aggregate is large compared with its rate of 

 formation, which is quite possible as its breakdown is in a different 

 way to the mode of its formation, 



f t is zero when * = ^ (1), 



, dz , 



and -r. = k^ps, 



so that we should have the action progressing after the short 

 time necessary to reach the stage (1) as a monomolecular reaction. 



Initially -=- is zero, as y is zero, and the velocity -=- increases 



until we reach the limiting value of y. 



In these experiments, in order to observe the initial stage the 

 action was allowed to proceed for some days to see if the same 

 constant for velocity would be obtained as in the first experiment 

 detailed, and also to see whether the additional hydrochloric acid in 

 the last experiment affected the general rate of the action. 



As the action takes a very considerable time to be nearly 

 completed it is necessary to find the value of the final conductivity 

 from experiments reached in a finite time. This can be done by 

 taking two observations at times such that one is twice the other. 

 Suppose that as before a is the final value of the increased con- 

 ductivity, x 1 the conductivity increase corresponding to time t 1} 

 and x 2 that to t 2 , then we have 



1 , a 1, a 

 - log = - log , 



Jj-\ Cv "™ JLr~\ I/O (Jj """" t//f> 



and if t 2 = 2^ 



a { a 



whence a (2^ — oc 2 ) = xf, 



/v. 2 



so that a = 





We find in this way for the experiment of figure 3 the results 

 in the following table, with a = 5460. 



