Nomenclature
CAS number: 7789-23-3
Potassium fluoride (KF).
FK; mol wt 58.10.
F 32.70%, K 67.29%.
KF.
Description and references
Prepd by thermal decompn of KHF2 or by neutralizing HF with K2CO3: Lange,
Eichler, Z. Phys. Chem. 129, 285, 286 (1927); Kwasnik in Handbook of
Preparative Inorganic Chemistry vol. 1, G.
Brauer, Ed. (Academic Press, New York, 2nd ed., 1963) p 236. Toxicity
data: Simonin, C. R. Seances Soc. Biol. Ses
Fil. 124, 133 (1937).
Properties
Cubic crystals (NaCl lattice). Usually obtained
as white, deliquesc powder or solid. Poisonous. d 2.481. mp 859.9°. bp 1505°. Soly in water (g/100 ml):
92.3 (18°); 96.4 (21°). Very freely sol in boiling water. Also
sol in aq HF, liquid NH3. Insol in alcohol unless water
is present. May be stored in aluminum containers. Attracts moisture
from the air. Aq solns corrode glass and porcelain. MLD in guinea pigs (mg/kg): 250 orally, 350 s.c.; in frogs (mg/kg): 375 s.c. (Simonin).Derivative
Dihydrate.
Nomenclature
CAS number: 13455-21-5
FK.2H
2O; mol wt 94.13.
F 20.18%, K 41.54%, H 4.28%, O 33.99%.
Properties
Monoclinic crystals, mp 41°. Soly in water (18°): 349.3 g/l00 ml.Derivative
Tetrahydrate.
Nomenclature
CAS number: 34341-58-7
FK.4H
2O; mol wt 130.16.
F 14.60%, K 30.04%, H 6.20%, O 49.17%.
Properties
Crystals, mp 19.3°.Caution
Irritating to skin, eyes, mucous
membranes.Use
In the fluorination of organic compds; in flux for
hard solder; to prevent unwanted fermentations; in insecticide formulations;
for frosting glass. Complexing agent.