Nomenclature
CAS number: 7705-08-0
Iron chloride (FeCl
3); iron(III) chloride; flores martis.
Cl
3Fe; mol wt 162.20.
Cl 65.57%, Fe 34.43%.
FeCl
3.
Description and references
Occurs in nature as the mineral molysite. Prepn: Tarr, Inorg. Synth. 3, 191 (1950); Pray, ibid. 5, 153 (1957); Epperson et al., ibid. 7, 163 (1963); Lieser, Elias, Z. Anorg. Allg. Chem. 316, 208
(1962); Attwood, Shelton, J. Inorg. Nucl.
Chem. 26, 1758 (1964); Bardawil et al., Inorg. Chem. 3, 149
(1964). Acute toxicity: C. S. Hosking, Aust.
Paediatr. J. 6, 92 (1970). Use as clinical
reagent: L. Cassidei et al., Clin.
Chim. Acta 90, 121 (1978).
Properties
Hexagonal, dark leaflets or plates. Red by transmitted
light, green by reflected light; sometimes appears brownish-black.
Very hygroscopic. Melts and volatilizes about 300°; bp ≈316°; d25 2.90. Vapor density measurements
show that it is dimeric at about 400° but monomeric above 750°. Dissociates
at high temps to FeCl2 and Cl2. Readily absorbs
water in air to form the hexahydrate. Readily sol in water, alcohol,
ether, acetone; slightly sol in CS2. Practically insol
in ethyl acetate. Corrosive. Keep well closed.Derivative
Hexahydrate.
Nomenclature
CAS number: 10025-77-1
Cl
3Fe.6H
2O; mol wt 270.30.
Cl 39.35%, Fe 20.66%, H 4.47%, O 35.51%.
Properties
Brownish-yellow or orange monoclinic crystals.
d 1.82. Structure:
trans-[FeCl2(H2O)4]Cl.2H2O: Lind, J. Chem. Phys. 47, 990 (1967). Usually slight odor of HCl; very hygroscopic.
mp ≈37°. Readily
sol in water, alcohol, acetone, ether; pH of 0.1 molar aq soln 2.0.
Keep well closed. LD50 i.v. in mice: 0.049 mg Fe/g (Hosking).Caution
Potential symptoms of overexposure
are irritation of eyes, skin, mucous membranes; abdominal pain, diarrhea,
vomiting; possible liver damage. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140,
1997) p 174.Use
In photoengraving; photography; manuf of other Fe
salts, pigments, ink; as catalyst in organic reactions; purifying
factory effluents and deodorizing sewage; chlorination of Ag and Cu
ores; as mordant in dyeing and printing textiles; oxidizing agent
in dye manuf. Clinical reagent (amino acids in urine, esp in phenylketonuria).
Therapeutic Category
Hexahydrate as astringent, styptic.
Therapeutic Category (Veterinary)
Styptic, astringent.
Keywords
Astringent