HYDROLYSIS OF UREA HYDROCHLORIDE. 131 



urea hydrochloride, the rate of hydrolysis of methyl acetate 

 was determined, first in a solution containing hydrochloric 

 acid, and then in a solution containing urea hydrochloride. 

 The rate of hydrolysis of methyl acetate was calculated 

 from the equation 



fr _ 1 4 a n + 2 n x (i 4 a n + 1 - 1) 



~ 1 1/4 an + 1 ° g 4 a «■- 2 n« (1 4an + 1 + 1) 



obtained by integrating — — = k (a-x) — /ci # 2 



Cv U 



where k = the rate of hydrolysis 



ki = the rate of esterification 



a = the initial concentration of ester 



x = amount of ester hydrolysed in time t (minutes) 



a - £ 



and £ = amount of ester hydrolysed from the beginning 

 of the reaction up to the equilibrium. The value of x was 

 found by determining the amount of acetic acid in the 

 solution after different intervals of time by titrating a 

 portion with baryta solution. 



The values of k found in any experiment were constant 

 to within about 2 per cent, of the mean. An example is 

 given in detail in Table VII for the rate of hydrolysis of 

 5 per cent, methyl acetate by N/2 hydrochloric acid and 

 M/2 urea in water at 25° 0. 



Table VII. 

 t x Jcx 10 4 





 30 

 60 " 

 91 

 120 

 150 

 212 

 270 

 332 



•0600 



9-14 



•1192 



9-20 



•1733 



9-09 



•2250 



9-23 



•2692 



9-10 



•3600 



9-19 



•4275 



9-03 



•4975 



9-10 





Mean 9-13 



