Title: Ammonium Hexafluorosilicate
CAS Registry Number: 16919-19-0
CAS Name: Diammonium hexafluorosilicate(2-)
Synonyms: ammonium fluosilicate; ammonium silicofluoride
Molecular Formula: F6H8N2Si
Molecular Weight: 178.15
Percent Composition: F 63.99%, H 4.53%, N 15.72%, Si 15.77%
Line Formula: (NH4)2SiF6
Literature References: Occurs in nature as the mineral
cryptohalite. Prepn:
Gmelins, Ammonium (8th ed.)
23, pp 414-415 (1936). Crystal structure: Schlemper
et al., J. Chem. Phys. 44, 2499 (1966);
45, 408 (1966). Toxicity study: Simonin, Pierron,
C.R. Seances Soc. Biol. Ses Fil. 124, 133 (1937).
Properties: Odorless crystalline powder. Two modifications at room temp: stable, cubic phase; metastable, trigonal phase. Freely sol in water. Practically insol in alcohol, acetone. LD orally in guinea pigs: 150 mg/kg (Simonin, Pierron).
Toxicity data: LD orally in guinea pigs: 150 mg/kg (Simonin, Pierron)
CAUTION: Toxic symptoms similar to sodium fluoride.
Use: In pesticides; in soldering flux; etching glass.
