60 Drushel and Lmhart — Metallic Alkyl Sulphates. 



Summary. — The experimental results lead to the following 

 conclusions : 



1. Ethyl barium sulphate and ethyl sulphuric acid decom- 

 pose extremely slowly in water solution even at moderately 

 high temperatures. 



2. Fair velocity constants are obtained on the hypothesis 

 that ethyl barium sulphate and ethyl sulphuric acid are esters 

 of similar stability in the presence of aqueous hydrochloric 

 acid, and that the reaction for their simultaneous decomposition 

 is molecular. 



3. The velocity constants are improved when dissociation 

 factors for the ester undergoing decomposition and the cata- 

 lyzing acid are introduced. 



4. In dilute aqueous hydrochloric acid the total concentration 

 of ethyl sulphate ions is apparently approximately equal to the 

 product of the total ester concentration (A— x+^x) and {d), 

 the degree of dissociation of ethyl barium sulphate of like 

 concentration in water solution. 



5. In strong aqueous hydrochloric acid (1*8N and 4N) the 

 formation of barium sulphate is probably chiefly due to the 

 hydrolysis of the ethyl sulphuric acid, liberated from the ethyl 

 barium sulphate by the hydrochloric acid, to sulphuric acid 

 and its subsequent combination with the barium chloride set 

 free from the ethyl barium sulphate, in which case d l may be 

 set equal to d„ in the velocity equation. 



