Qualitative Tests. 73 
Interfering Elements. 
Sodiwm.—(a) The flame through blue glass will 
be violet or blue; 
(b) A bead of borax and a little boracic acid made 
brown by nickel will become blue on addition of a po- 
tassium compound. 
Lithiwum.—The flame through green glass will be 
bluish green. 
IN THE WET WAY. 
1. PtCl: with HCl precipitates yellow crystalline 
(KCl):PtCl.. Evaporate to dryness. The precipitate 
is not dissolved by alcohol. 
Confirm.—By blowpipe and spectroscope. 
SELENIUM, Se. 
WITH THE BLOWPIPE. 
On Coal, R. F.—Disagreeable horse-radish odor, 
- brown fumes, and a volatile steel-gray coat with a red 
border. 
In Open Tube.—Steel-gray sublimate with red bor- 
der, sometimes white crystals. 
In Closed Tube.—Dark-red sublimate and horse- 
radish odor. 
Flame.—Azure-blue. 
On Coal, with Soda.—Thoroughly fuse in R. F., 
place on bright silver, moisten, crush, and let stand. The 
silver will be blackened. 
IN THE WET WAY. 
1. HS precipitates yellow sulphide of selenium, 
soluble in (NH:):8. Upon heating the precipitate turns 
reddish yellow. 
2. SnCl+HCl produces a red precipitate of Se, 
which turns gray at a high temperature. 
3. Metallic copper, when placed in a warm solu- 
tion of selenious acid, containing HCl, becomes black; 
