THE ANALYSIS OF CADMIUM BROMIDE. 



29 



value 112.417 (Ag = 107.880). If the atomic weight of silver is 107. S70, then 

 the atomic weight of cadmium is 112.407. 



Fraction. 



I . . . 

 I ... 



II, Series i 

 II, Series i 

 II, Series 2 

 II, Series 2 

 II . . . 

 II . . . 



Ill ... 



Ill ... 



Ratio. 



CdClj 

 CdCla : 

 CdCl2 

 CdCla : 

 CdCla : 

 CdClo ; 

 CdBr2 

 CdBra : 

 CdBra 

 CdBr2 



2Ag 



2AgCl 



2Ag 



2AgCl 



2Ag 



2AgCl 



2Ag 



2AgBr 



2Ag 



2AgBr 



Average 



Atomic 

 weight. 



I12.41S 

 I12.41Q 

 112.403) 

 112.429 I 

 I12.418 I 

 I12.418 • 

 II2.418 

 I12.414 

 112.423 > 

 112.413) 



I12.417 



Average. 



I12.417 

 I12.416 

 II2.418 

 I12.416 

 I12.418 



I12.417 



Attention should be called to the agreement with ours of the results of Morse 

 and Arbuckle's synthesis of cadmium oxide, which yielded the value 112.38, and 

 of Bucher's painstaking work upon the halogen compounds of cadmium. 

 Bucher's values from cadmium chloride vary between 112. 21 and 112.41, with 

 an average of 112.32, but if the first 7 of his 21 experiments are rejected, his 

 average becomes 112.35, ^^^ ^ o^ ^^ results are as high as 112.38. His analyses 

 of the bromide vary between 112.25 ^^^^ 112.41, with an average of 112.34. 



The results of this investigation are then as follows: 



(i) The value for the atomic weight of cadmium previously found by analy- 

 sis of cadmium chloride, 112.42 (Ag = 107.880), is supported by the analysis of 

 cadmium bromide. If silver is 107.870, cadmium becomes 1 12.41. 



(2) It is pointed out that phosphorus pentoxide is not perceptibly attacked 

 by hydrobromic-acid gas which is diluted with twice its volume of nitrogen. 



