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| Names | |
|---|---|
| IUPAC name Iron(III) sulfate | |
| Other names Ferric sulfate | |
| Identifiers | |
3D model (JSmol) | |
| ChEBI | |
| ChemSpider |
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| ECHA InfoCard | 100.030.054 |
| RTECS number |
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| UNII | |
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| Properties | |
| Fe2(SO4)3 | |
| Molar mass | 399.88 g/mol (anhydrous) 489.96 g/mol (pentahydrate) 562.00 g/mol (nonahydrate) |
| Appearance | grayish-white crystals |
| Density | 3.097 g/cm3 (anhydrous) 1.898 g/cm3 (pentahydrate) |
| Melting point | 480 °C (896 °F; 753 K) (anhydrous)(decomposes) 175 °C (347 °F) (nonahydrate) |
| 256 g/L (monohydrate, 293 K) | |
| Solubility | sparingly soluble inalcohol negligible inacetone,ethyl acetate insoluble insulfuric acid,ammonia |
Refractive index (nD) | 1.814 (anhydrous) 1.552 (nonahydrate) |
| Hazards | |
| NFPA 704 (fire diamond) | |
| Lethal dose or concentration (LD, LC): | |
LD50 (median dose) | 500 mg/kg (oral, rat) |
| NIOSH (US health exposure limits): | |
REL (Recommended) | TWA 1 mg/m3[1] |
| Related compounds | |
Otheranions | Iron(III) chloride Iron(III) nitrate |
Related compounds | Iron(II) sulfate |
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |
Iron(III) sulfate orferric sulfate (British English:sulphate instead of sulfate) is a family ofinorganic compounds with the formula Fe2(SO4)3(H2O)n. A variety ofhydrates are known, including the most commonly encountered form of "ferric sulfate". Solutions are used in dyeing as amordant and as a coagulant for industrial wastes. Solutions of ferric sulfate are also used in the processing of aluminum and steel.[2][3]
The various crystalline forms of Fe2(SO4)3(H2O)n are well-defined, often byX-ray crystallography. The nature of the aqueous solutions is often less certain, butaquo-hydroxo complexes such as [Fe(H2O)6]3+ and [Fe(H2O)5(OH)]2+ are often assumed.[4] Regardless, all such solids and solutions feature ferric ions, each with five unpaired electrons. By virtue of thishigh-spin d5 electronic configuration, these ions areparamagnetic and are weak chromophores.
Ferric sulfate solutions are usually generated from iron wastes. The actual identity of the iron species is often vague, but many applications do not demand high-purity materials. It is produced on a large scale by treating sulfuric acid, a hot solution offerrous sulfate, and anoxidizing agent. Typical oxidizing agents includechlorine,nitric acid, andhydrogen peroxide.[5]
Iron sulfates occur as a variety of rare commercially unimportant minerals. The mineralogical form of iron(III) sulfate,mikasaite, is a mixed iron-aluminium sulfate with the chemical formula (Fe3+, Al3+)2(SO4)3.[6] This anhydrous form occurs very rarely and is connected with coal fires. The hydrates are more common, withcoquimbite[7] (nonahydrate) as probably the most often met among them.Paracoquimbite is the other, rarely encountered natural nonahydrate.Kornelite (heptahydrate) andquenstedtite (decahydrate) are rarely found. Andradite garnet is a yellow-green example found in Italy.[8]Lausenite (hexa- or pentahydrate) is a doubtful species. All the mentioned natural hydrates are unstable connected with the weathering (aerobic oxidation) of Fe-bearing primary minerals (mainlypyrite andmarcasite).
