58 PROCEEDINGS OP THE AMERICAN ACADEMY 



Analysis op Iodide of Antimony. 

 Iodine Determinations. 



Theory Sb= 120, requires . . 76.047 

 Theory Sb= 122, „ . . 75.744 



If in calculating the results of these iodine determinations we use 

 the atomic weights of Stas, 1= 126.85 and Ag = 107.93, the mean 

 value would be 76.034, and the corresponding atomic weight of 

 antimony 119.95. 



The difference (0.004) between the first mean value and theory — 

 corresponding to only about ^jj of a milligramme in the largest amount 

 of argentic iodide weighed — is evidently insignificant, so that these 

 results confirm the lower value of the atomic weight of antimony as 

 closely as did the analyses of the bromide.* 



* After the success we had in the application of oqr method of sublimation to 

 purifying the iodide, we attempted to purify the bromide of antimony in the 

 same way. We thus obtained a very beautiful product, free from every trace 

 of impurity except hygroscopic moisture. The last could not be avoided with- 

 out more efficient means than we then had of drying the necessarily somewhat 

 rapid gas current; but we were satisfied that with proper precautions, this 

 would be a better method of preparing pure antimonious bromide than the one 



