ANTIMONY. 217 



28.485 

 28.492 

 28.481 



Mean, 28.520, db .008 



Hence, if S = 32, Sb = 120.3. 



Immediately after the appearance of Schneider's memoir, Rose* pub- 

 lished the result of a single analysis of antimony trichloride, previously 

 made under his supervision b} 7 Weber. This analysis, if Cl = 35.5, makes 

 Sb = 120.7, a value of no great weight, but in a measure confirmatory of 

 that obtained by Schneider. 



The next research upon the atomic weight of antimony was that of 

 Dexter,f published in 1857. This chemist, having tried to determine 

 the amount of gold precipitable by a known weight of antimony, and 

 having obtained discordant results, finally resorted to the original method 

 of Berzelius. Antimony, purified with extreme care, was oxidized by 

 nitric acid, and the gain in weight was determined. From 1.5 to 3.3 

 grammes of metal were used in each experiment. The reduction of the 

 weights to a vacuum standard was neglected as being superfluous. From 

 the data obtained, we get the following percentages of Sb in Sb. 2 4 : 



79.268 

 73.272 



79-255 

 79.266 



79-253 

 79.271 

 79.264 

 79.260 

 79.286 



79-274 

 79.232 



79-395 

 79-379 



Mean, 79.283, .009 



Hence, if = 16, Sb = 122.46. 



The determinations of Dumas J were published in 1859. This chemist 

 sought to fix the ratio between silver and antimonious chloride, and ob- 

 tained results for the atomic weight of antimony quite near to those of 

 Dexter. The SbCl 3 was prepared by the action of dry chlorine upon 

 pure antimony; it was distilled several times over antimony powder, 

 and it seemed to be perfectly pure. Known weights of this preparation 

 were added to solutions of tartaric acid in water, and the silver chloride 

 was precipitated without previous removal of the antimony. Here, as 



* Poggend. Annalen, 98, 455. 1856. 

 t Poggend. Annalen, 100, 363. 1857. 

 I Ann. Chim. Phys. (3), 55, 175. 



