Ammonium iron(II) sulfate
Ammonium iron(II) sulfate Identifiers CAS number , (anhydrous)
PubChem ChemSpider EC number Jmol-3D images Image 1 Properties Molecular formula (NH4)2Fe(SO4)2·6H2O Molar mass 284.05 g mol−1 (anhydrous)
392.14 g mol−1 (hexahydrous)
Appearance Blue-green solid Melting point
100-110 °C, 373-383 K, 212-230 °F
Hazards MSDS Fisher MSDS R-phrases S-phrases Main hazards Irritant (Xi) NFPA 704 Related compounds Related compounds Ammonium iron(III) sulfate (what is: /?)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Ammonium iron(II) sulfate, or Mohr's Salt, is the inorganic compound with the formula (NH4)2Fe(SO4)2·6H2O. Containing two different cations, Fe2+ and NH4+, it is classified as a double salt of ferrous sulfate and ammonium sulfate. It is a common laboratory reagent. Like the other ferrous sulfate salts, ferrous ammonium sulfate dissolves in water to give the aquo complex [Fe(H2O)6]2+, which has octahedral molecular geometry.
In analytical chemistry, this salt is preferred over other salts of ferrous sulfate for titration purposes as it is much less prone to oxidation by air to iron(III). The oxidation of solutions of iron(II) is very pH dependent, occurring much more readily at high pH. The ammonium ions make solutions of Mohr's salt slightly acidic, which slows this oxidation process.
Mohr's salt is named after the German chemist Karl Friedrich Mohr, who made many important advances in the methodology of titration in the 19th century. Several similar salts are known, which were once called Tutton's salts.
Preparation of Mohr's salt
Mohr's salt is prepared by dissolving an equimolar mixture of hydrated ferrous sulfate and ammonium sulfate in water containing a little sulfuric acid, and then subjecting the resulting solution to crystallization. Ferrous ammonium sulfate forms light green crystals.
Shape of ferrous ammonium sulfate crystals
The crystals of Mohr's salt are monoclinic in shape.
Wikimedia Foundation. 2010.
Look at other dictionaries:
Iron(II) sulfate — Other names Ferrous sulfate; green vitriol; iron vitriol; copperas; melanterite; szomolnokite … Wikipedia
Ammonium sulfate — Ammonium sulfate … Wikipedia
Ammonium chloride — IUPAC name … Wikipedia
Ammonium bicarbonate — Ammonium bicarbonate … Wikipedia
Ammonium carbonate — Chembox new Name = Ammonium carbonate ImageFile =ammonium carbonate.png ImageName = IUPACName = Ammonium carbonate Section1 = Chembox Identifiers CASNo = 506 87 6 Section2 = Chembox Properties Formula = (NH4)2CO3 MolarMass = 96.09 g/mol… … Wikipedia
iron ammonium sulfate — geležies amonio alūnas statusas T sritis chemija formulė (NH₄)Fe(SO₄)·12H₂O atitikmenys: angl. ammonio feric sulfate; ferric ammonium alum; iron ammonium sulfate rus. железо аммониевые квасцы ryšiai: sinonimas – amonio geležies… … Chemijos terminų aiškinamasis žodynas
iron processing — Introduction use of a smelting process to turn the ore into a form from which products can be fashioned. Included in this article also is a discussion of the mining of iron and of its preparation for smelting. Iron (Fe) is a… … Universalium
iron blue — noun 1. slightly purplish or bluish dark grey • Syn: ↑steel grey, ↑steel gray, ↑Davy s grey, ↑Davy s gray • Hypernyms: ↑gray, ↑grayness, ↑grey, ↑greyness … Useful english dictionary
Iron — An essential mineral. Iron is necessary for the transport of oxygen (via hemoglobin in red blood cells) and for oxidation by cells (via cytochrome). Deficiency of iron is a common cause of anemia. Food sources of iron include meat, poultry, eggs … Medical dictionary
iron alum — noun 1. : an alum containing iron as the trivalent constituent; especially : ammonium ferric alum NH4Fe(SO4)2.12H2O 2. [alum (I) (aluminum sulfate)] … Useful english dictionary