17 
Preparation I. 
0-5900 gram substance gave 0-4870 gram silver chloride and 
0-0069 gram metallic silver. 
Preparation II. 
0-493 gram substance gave 0-4250 gram silver chloride. 
Prep. 1 20-80 % Cl. 
Prep. II 21-32 % 
Mean 21-06. 
In order to determine the amount of chromium it con- 
tains a weighed portion of the substance was repeatedly- 
heated with strong hydrochloric acid on a water-bath until 
the evolution of chlorine entirely ceased : the soluti on was 
then diluted with water, heated to boiling, ammonia added 
in slight excess, and again boiled until the supernatant 
liquid appeared perfectly colourless. The precipitated 
chrome sesquioxide was then filtered, dried, and weighed. 
Preparation I. 
0-3442 grm. substance gave 0-2470 grm. chrome sesquioxide. 
0-5900 „ „ „ 0-4235 „ 
Preparation II. 
0-5082 grm. substance gave 0-3590 grm. chrome sesquioxide. 
0-5942 
0-4210 
>» 
Prep. I. 49-30% Cr. 
49-25 % 
Prep. II. 48-45% 
48-62 % 
Mean 48-91 % 
Hence the percentage composition of the substance is as 
follows : — 
Chlorine 
Found. 
... 21-06 . 
Ratios. 
2 ... 
Calculated. 
... 21-86 
Chromium ... 
... 48-91 .. 
. . . , , 3 . . . 
... 48-54 
Oxygen 
... 30 03 . 
..... 6 ... 
... 29-60 
100-00 
10-000 
