248 



THE ATOMIC WEIGHTS. 



The following ratios are now available for computing the atomic weight 

 of chromium : 



(2- 



(3. 

 (4- 

 (5. 

 (6. 

 (7. 

 (S- 

 (9. 



(lO. 



(.1. 



(12. 



(•3 

 (H. 

 (15- 

 (i6. 



(17. 



(i8. 



Percentage Cr^Oj from Ag2CrO^, 22.934, zt .0018 

 Percentage Cr^Og from Ag^Cr^O,, 35.236, =b .0335 

 2AgCl : Ag.^CrO^ : : 100 : 1 15.760, zt .0069 

 2AgCl : Ag./'r207 : : 100 : 150.816, d= .074 

 4AgCl : Cr^Oj : : lOO : 26.620, =b .0052 

 Percentage CrjOj in Cr2(SOj3, 38.838, zb .0087 

 Percentage Cr^O, in AmCr( 80^)2- 12 HjO, 16.143, ± •0125 

 BaSO^ : BaCrO^ ; : 100 : 108.9815, dz .0369 

 BaCrO^ : BaClg : : 100 : 81.702, dz .014 

 3AgCl : CrClg : : 100 : 36.842, zh .0031 

 2KCIO3 : KjCr^O, : : 100 : 120.216, zh .0235 

 Percentage Cr203 in Ag2Cr04.4NH3, 19.059, zb .0074 

 2AgCl : Ag2Cr0^.4NH3 : : 100 : 139.357, ± .1109 

 Percentage ^^03 in Am^Cr^O,, 60.337, zt .0029 

 AgjCrO^ : 3I : : lOO : 1 14.630, zfc .015 

 Ag2Cr0^.4NH3 : 3I : : 100 : 95.208, ziz .0497 

 2K2Cr20j : KHl20g : : 100 : 66.212, zb .0044 

 2Am2Cr20j : KHL^g : : 100 : 77.268, zb .0041 



The antecedent values to use in the reduction are — 



= 15 879, zb .0003 



Ag = 107. 108, zb .0031 

 CI = 35.179. ±.0048 



1 = 125.888, zb .0069 

 K =r 38.817, zb .0051 



.S = 31.828, zb .0015 



N = 13.935, zb .0021 

 Ba = 136.392, zb .0086 

 AgCI = 142.287, zb .0037 



For the molecular weight of Cr.^O., seven values are now calculable, as 

 follows. : 



From (i) Cr203 = 151.120, zb .0130 



From (2) " := 151. 105, zb .1636 



From (5) ., " = 151.507, zb .0299 



From (6) " = 151.384, zb .0341 



From (7) ".=- 153.756, ±.1205 



From (12) " = 151.478, zb .0606 



From (r 4) " =^ 151.190, zi= .01 10 



General mean Cr203 = 151.229, zb .0039 



For silver chroraate there are two values — 



From (3) Ag2CrO^ = 329.423, zb .0195 



F"rom (15) " = 329.464, zb .0467 



General mean AgjCrO^ := 329.430, zb .0180 



And for the ammonio-chromate we have — 



From (13) Ag2Cr0^.4NH3 = 396.574, ± .3158 



From (16) " z= 396.673, ±z .2082 



General mean.... Ag2Cr04.4NH3 = 396.647, zb .1738 



