vm, a, 1 Gibbs, Williams, Galajikian: Methyl Salicylate IV 21 



VII. THE HYDROLYSIS OF METHYL SALICYLATE IN WATER 

 MEASUREMENTS AT 30° 



The methyl salicylate employed was especially purified by 

 shaking with sodium hydrogen carbonate solution, drying over 

 fused calcium chloride, and distilling at 6 millimeters' pressure. 



A few determinations carried on without precautions to insure 

 great accuracy showed that saturated solutions of salicylic acid 

 in water and in methyl salicylate contained at 30° about 0.32 

 gram per 100 cubic centimeters of the former solvent and 9.81 

 grams in the latter, a ratio of about 1 to 30 or 31. Saturated 

 aqueous solutions of salicylic acid shaken with methyl salicylate 

 until equilibrium was reached have the following distribution 

 of salicylic acid. 



One volume water and one-half volume methyl salicylate 

 gave 6 per cent of the salicylic acid in the water and 94 per 

 cent in the ester as the average of a number of determinations. 



One volume of water and one volume of ester gave about 3 

 per cent in the water and 97 per cent in the ester, a ratio of 

 about 1 to 32. 



Conductivity measurements. — Conductivity measurements 

 were made at 30° in small cells in one end of which the electrodes 

 were sealed (fig. 4). After the introduction of the solution, 

 the other end was sealed. 



Fig. 4. — Conductivity cell. 



The cells were standardized at 30° by means of N/50 potas- 

 sium chloride solution, and the data given in Kohlrausch and 

 Holborn 1T and the Kohlrausch methods and standards were 

 employed in the manipulation. 



It is realized that measurements at 30° introduce some com- 

 plications, but at lower temperature a serious error was some- 

 times encountered, because of the construction of the cell which 

 permitted a short circuit at the point where the electrodes were 

 sealed into the glass due to the condensation of moisture from 

 the humid atmosphere of this locality. 



The first conductivity measurements, recorded in Table VIII, 

 were made in a cell charged with 15 cubic centimeters of water 



"Das Leitvermogen der Elektrolyte. Leipzig (1898). 



