Iron(III) sulfate
{{For|the other sulfate of iron, also named ferrous sulfate|Iron(II) sulfate}}
{{chembox
| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 451998549
| Name = Iron(III) sulfate
| ImageFile = Síran železitý.JPG
| ImageSize = 250px
| ImageName = Iron(III) sulfate
| IUPACName = Iron(III) sulfate
| OtherNames = Ferric sulfate
| SystematicName =
| Section1 = {{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 23211
| InChI = 1/2Fe.3H2O4S/c;;3*1-5(2,3)4/h;;3*(H2,1,2,3,4)/q2*+3;;;/p-6
| InChIKey = RUTXIHLAWFEWGM-CYFPFDDLAR
| ChEBI_Ref = {{ebicite|correct|EBI}}
| ChEBI = 53438
| SMILES = [Fe+3].[Fe+3].[O-]S(=O)(=O)[O-].[O-]S([O-])(=O)=O.[O-]S([O-])(=O)=O
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/2Fe.3H2O4S/c;;3*1-5(2,3)4/h;;3*(H2,1,2,3,4)/q2*+3;;;/p-6
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = RUTXIHLAWFEWGM-UHFFFAOYSA-H
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 10028-22-5
| UNII_Ref = {{fdacite|changed|FDA}}
| UNII = 4YKQ1X5E5Y
| PubChem = 24826
| RTECS = NO8505000
}}
| Section2 = {{Chembox Properties
| Formula = Fe2(SO4)3
| MolarMass = 399.88 g/mol (anhydrous)
489.96 g/mol (pentahydrate)
562.00 g/mol (nonahydrate)
| Appearance = grayish-white crystals
| Solubility = 256g/L (monohydrate, 293K)
| SolubleOther = sparingly soluble in alcohol
negligible in acetone, ethyl acetate
insoluble in sulfuric acid, ammonia
| MeltingPtC = 480
| MeltingPt_notes = (anhydrous)(decomposes)
{{convert|175|C}} (nonahydrate)
| Density = 3.097 g/cm3 (anhydrous)
1.898 g/cm3 (pentahydrate)
| RefractIndex = 1.814 (anhydrous)
1.552 (nonahydrate)
}}
| Section3 = {{Chembox Hazards
| MainHazards =
| FlashPt =
| ExternalSDS =
| NFPA-H = 1
| NFPA-F = 0
| NFPA-R = 0
| LD50 = 500 mg/kg (oral, rat)
| REL = TWA 1 mg/m3{{PGCH|0346}}
}}
| Section4 =
| Section5 =
| Section6 =
| Section8 = {{Chembox Related
| OtherAnions = Iron(III) chloride
Iron(III) nitrate
| OtherCompounds = Iron(II) sulfate
}}
}}
Iron(III) sulfate or ferric sulfate (British English: sulphate instead of sulfate) is a family of inorganic compounds with the formula Fe2(SO4)3(H2O)n. A variety of hydrates are known, including the most commonly encountered form of "ferric sulfate". Solutions are used in dyeing as a mordant, and as a coagulant for industrial wastes. Solutions of ferric sulfate are also used in the processing of aluminum and steel.[http://www.encyclopedia.com/doc/1E1-ferricsu.html Ferric sulfate]. The Columbia Encyclopedia, Sixth Edition. Retrieved November, 2007.{{Ullmann | doi = 10.1002/14356007.a14_591 | title = Iron Compounds | year = 2000 | last1 = Wildermuth | first1 = Egon | last2 = Stark | first2 = Hans | last3 = Friedrich | first3 = Gabriele | last4 = Ebenhöch | first4 = Franz Ludwig | last5 = Kühborth | first5 = Brigitte | last6 = Silver | first6 = Jack | last7 = Rituper | first7 = Rafael }}
Speciation
The various crystalline forms of Fe2(SO4)3(H2O)n are well-defined, often by X-ray crystallography. The nature of the aqueous solutions is often less certain, but aquo-hydroxo complexes such as [Fe(H2O)6]3+ and [Fe(H2O)5(OH)]2+ are often assumed.{{cite journal |doi=10.1021/ic50215a014|title=Kinetics of Solvent Water Exchange on Iron(III) |year=1981 |last1=Grant |first1=M. |last2=Jordan |first2=R. B. |journal=Inorganic Chemistry |volume=20 |pages=55–60 }} Regardless, all such solids and solutions feature ferric ions, each with five unpaired electrons. By virtue of this high spin d5 electronic configuration, these ions are paramagnetic and are weak chromophores.
Production
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 of ferrous sulfate, and an oxidizing agent. Typical oxidizing agents include chlorine, nitric acid, and hydrogen peroxide.[http://www.britannica.com/eb/article-3562/iron#93315.hook Iron compounds]. Encyclopædia Britannica Article. Retrieved November, 2007
:{{chem2 | 2 FeSO4 + H2SO4 + H2O2 -> Fe2(SO4)3 + 2 H2O }}
Natural occurrences
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.[http://un2sg4.unige.ch/athena/cgi-bin/minfich?s=Mikasaite Mikasaite] This anhydrous form occurs very rarely and is connected with coal fires. The hydrates are more common, with coquimbite{{Cite web |title=Minerals Colored by Metal Ions |url=http://minerals.gps.caltech.edu/color_causes/Metal_Ion/index.html |access-date=2023-03-01 |website=minerals.gps.caltech.edu}} (nonahydrate) as probably the most often met among them. Paracoquimbite is the other, rarely encountered natural nonahydrate. Kornelite (heptahydrate) and quenstedtite (decahydrate) are rarely found. Andradite garnet is a yellow-green example found in Italy.{{Cite web |title=Minerals Colored by Metal Ions |url=http://minerals.gps.caltech.edu/color_causes/Metal_Ion/index.html |access-date=2023-03-01 |website=minerals.gps.caltech.edu}} 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 (mainly pyrite and marcasite).
See also
- Iron(II) sulfate or ferrous sulfate
- Ammonium iron(II) sulfate
- Ammonium iron(III) sulfate
References
{{reflist}}
External links
- [https://hazard.com/msds/f2/ckb/ckbtk.html Material Safety Data Sheet]
{{Iron compounds}}
{{Sulfates}}