8C 



MOLECULAR WEIGHT OF ARGENTIC SULPHATE, ETC. 



THE FINAL RESULTS. 



Having shown the feasibility of the plan of operations and gained prac- 

 tice by three preliminary experiments, a final series was undertaken, whose 

 outcome is detailed below. 



Sample A of argentic sulphate was used in experiments 4 and 5 and 

 sample B in the remainder. In experiments 5 and 6 the hydrochloric acid 

 was generated from ammonic chloride, and in the other experiments from 

 concentrated hydrochloric acid. The corrected weight of argentic chloride 

 was obtained by adding the trace found in the condenser to the average 

 weight after fusion in hydrochloric acid. In experiments 4, 5, and 7 the 

 correction for the argentic chloride in the condenser was not determined 

 directly, but the mean of the other determinations (0.00004 gram) was 

 added. 



In experiments 8 and 9 the narrow exit tube became completely blocked 

 by the creeping of the argentic chloride. This made it necessary to fuse 

 the solid while there was still present considerable argentic sulphate; and 

 therefore the sulphuric acid boiled and material was lost by being pro- 

 jected out of the tube. The first of these was rejected, and the second not 

 finished. All the other determinations are recorded in full in the table. 

 The weighings have of course been corrected to the vacuum standard. 



The Quantitative Conversion of Argentic Sulphate to Chloride. 



Thus 100.000 parts of colorless argentic sulphate were found to yield 

 91.933 parts of argentic chloride, with a vanishingly small "probable 

 error." If the weight of the darkened samples are used in the calculation 

 the result becomes 91.934, a value which certainly represents the maxi- 

 mum. To have reduced the chief uncertainty to within such narrow limits 

 was to have solved the problem as far as it need be solved at present. 

 The interpretation of the result alone remains. 



