PRELIMINARY TESTING OF SOLIDS IN MINERAL SPAGYRICS
1.- Heat a small quantity of the substance in a test tube
OBSERVATION |
INDICATION |
Decrepitating |
NaCl, Pb(NO3)2, K2SO4, Zinc blended |
Carbonization, burnt odor and formation of water |
Organic matter, tartrates and other organic acids and salts |
Water given off |
Water mechanically inclosed, water of hydration and hydroxide |
Gases given off: |
|
Colorless and odorless: O- kindles a spark |
Chlorates, peroxides, oxides, nitrates |
CO- burns with blue flame |
Oxalates |
CO2- turns limewater turbid |
Carbonates, oxalates and organic matter |
Colorless with odor: NH3- turns red litmus blue |
Ammonium salts and organic compounds containing nitrogen |
SO2- recognized by odor |
Sulphur, sulphides, sulphites, sulphates |
(CN)2- almonds odor and burns with reddish flame |
Cyanides |
H2S- recognized by odor |
Moist sulphides |
Acetone- recognized by odor |
Acetates |
Colored gases: NO2- reddish brown; turns starch KI paper blue |
Nitrates of heavy metals |
Cl,Br, I- recognized by particulars color and odor |
Chlorides, bromides and iodides in the presence of oxidizing agents |
A sublimate forms: White |
Ammonium salts, HgCl, HgCl2, As2O3,Sb2O3 |
Yellow |
As2S3, HgO (with globules of Hg) |
Yellow becoming red when rubbed |
HgI2 |
Reddish brown drops, yellow when cold |
S |
Black with garlic odor |
As |
Black with violet vapor |
I |
Substance changes color: Becomes black |
Cu, Ni, Co, Mn salts |
Becomes dark red |
Salts of Fe |
Black (hot) and red (cold) with metallic globules |
Salts of Hg |
Dark red (hot), yellow (cold) |
PbCrO4 |
Yellow (hot), white (cold ) |
ZnO |
2.- Put a small quantity of the substance in a test tube, add a little dilute Chlorhidric acid, and heat gently
OBSERVATION |
INDICATION |
CO2 effervescence, turns limewater turbid |
Carbonates |
SO2 recognized by odor |
Sulphites |
SO2 with separation of S |
Thiosulphates |
H2S recognized by odor and lead acetate |
Sulphides |
NO2 brown, turns starch KI paper blue |
Nitritos |
HCN almonds odor |
Cyanides |
3.- Mix with anhydrous sodium carbonate and heat on charcoal
OBSERVATION |
INDICATION |
Metallic globule forms without incrustation |
|
Yellow |
Gold |
Red |
Cooper |
White and malleable |
Silver |
Metallic globule with incrustation |
|
Malleable |
Pb, Sn |
Brittle |
Sb, Bi |
Dark and brittle magnetic mass |
Fe, Co, Ni |
Lixandram