ATOMIC AVEIGHTS 



185 



Mean, 114.694 

 Mean of all as one series, 114.689, ± .0012 



Hence Sr = 87.614. 



For the ratio, measured gravimetrically, 2i^gBr : SrBr^ : : 100 : x, two 

 series of determinations are given : 



wt. AgBr. 



2.4415 

 2.8561 

 6.9337 



First Series. 



Wt. SrBr,. 



1.6086 



1.8817 



4.5681 



Ratio. 

 65.886 

 65.884 

 65.883 



Mean, 65.883 

 Mean of all as one series, 65.884. ± .0006 



Hence Sr=: 87.621. 



From the two bromide ratios the silver bromine ratio can be calculated, 

 with the following result : Ag : Br : : 100 : 74.077. 

 There are now five ratios for strontium, as follows: 



(1). 2Ag:SrCL:: 100: 73.4766, ± .0008 

 (2). 2Ag:SrCL.6H,0: : 100: 123.460, ± .0082 

 (3). SrCL:SrSO,: 1100:115.936, ± .0040 

 (4). 2Ag:SrBr„: : 100: 114.689, ± .0012 

 (5). 2AgBr:SrBro: :100:65.884, it .0006 



