OSMIUM. 323 



Hence we have for the percentage of osmium and for the osmichloride 

 proportional to 100 parts of AgCl 



Per cent. Os. AgCl : Salt. 



43.446 51.266 



43.484 $1.32 



43-458 51-254 



43-453 5L293 



Mean, 51.283, .0099 



In a later paper * two more reductions are given, in which only osmium 

 was estimated. 



Sail. Os. Percent. Os. 



2.6687 1.1597 43.45 6 



2.6937 1.1706 43-457 



These determinations, included with the previous four as one series, 

 give a mean percentage of Os in Am 2 OsCl 6 of 43.459, .0036. 



Secondly, potassium osmichloride was treated in the same way, but 

 the residue weighed consisted of Os + 2KC1. From this the potassium 

 chloride was dissolved out, recovered by evaporating the solution, and 

 weighed separately. The volatile portion, 4HC1, was also measured by 

 precipitation as silver chloride. In Seubert's first paper these data are 

 given : 



Os. 2KCI. 4AgCl. 



2.5148 ..... .7796 2.9837 



2.1138 .8405 .6547 2.5076 



Hence, with salt proportional to 100 parts of AgCl in the last column 

 we have 



Per cent. Os. Per cent. KCl. AgCl : Salt. 



...... 31.000 84.091 



39.762 3 .973 84.102 



Mean, 84.097, .0030 



In his second paper Seubert gives fuller data relative to the potassium 

 osmichloride, but treats it somewhat differently. The salt was reduced 

 by a stream of hydrogen as before, but after that the boat containing the 

 Os -{- 2KC1 was transferred to a platinum tube, in which, by prolonged 

 heating in the gas, the potassium chloride was completely volatilized. 

 The determinations of 4C1 as 4 AgCl were omitte \. Two series of data 

 are given, as follows : 



*Ann. d. Chem., 261, 258. 



