Qualitative Tests. 75 
If the litharge is dark, or if the button freezes be- 
fore brightening, or if it brightens but is not spherical, 
rescorify it on coal with borax, add more test-lead, and 
again cupel, until there remains only a white spherical 
button of silver. 
Dissolve button in HNO: in a glass and if gold is 
present it will fall to the bottom as a black powder. 
IN THE WET WAY. 
1. HCl precipitates white AgCl, insoluble in 
HNOs:, soluble in NH:OH. 
2. Cu precipitates metallic Ag. 
3. KI precipitates yellow AglI, insoluble in NH: 
OH, soluble in excess of reagent. 
Confirm.—By blowpipe test. 
SODIUM, Na. 
WITH THE BLOWPIPE. 
Flame.—Reddish yellow. 
IN THE WET WAY. 
1. (NaCl):PtCk crystallizes from its concentrated 
solutions in red prisms. 
2. KSbOs (in neutral or alkaline solutions) pre- 
cipitates white NaSbOs. The reagent should be dis- 
solved as wanted, as it is unstable in solution. 
Confirm.—By blowpipe and spectroscope. 
STRONTIUM, Sr. 
WITH THE BLOWPIPE. 
On Coal, with Soda.—tInsoluble, absorbed by the 
coal. 
Flame.—tIntense crimson, improved by moistening 
with HCl. 
With Borax or 8S. Ph.—Clear and colorless; can be 
flamed opaque. 
Interfering Elements. 
Barium.—The red flame may show upon first in- 
troduction of the sample into the flame, but it is after- 
wards turned brownish yellow. 
