:Manganese(II) carbonate
{{chembox
| Watchedfields = changed
| verifiedrevid = 402382106
| Name = Manganese(II) carbonate
| ImageFile1 =
| ImageFile2 = Manganese (II) Carbonate.jpg
| ImageSize =
| ImageName = Impure sample of MnCO3
| IUPACName = Manganese(II) carbonate
| OtherNames =
|Section1={{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 11233
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = 9ZV57512ZM
| InChI = 1/CH2O3.Mn/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2
| InChIKey = XMWCXZJXESXBBY-NUQVWONBAJ
| SMILES = [Mn+2].[O-]C([O-])=O
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/CH2O3.Mn/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = XMWCXZJXESXBBY-UHFFFAOYSA-L
| CASNo = 598-62-9
| CASNo_Ref = {{cascite|correct|CAS}}
| PubChem = 11726
| EINECS = 209-942-9
| RTECS =
}}
|Section2={{Chembox Properties
| Formula = MnCO3
| MolarMass = 114.95 g mol−1
| Appearance = White to faint pink solid
| Density = 3.12 g/cm3
| Solubility = negligible
| SolubilityProduct = 2.24 x 10−11
| SolubleOther = soluble in dilute acid, CO2
insoluble in alcohol, ammonia
| MeltingPtC = 200-300
| MeltingPt_notes =
decomposes{{Sigma-Aldrich|id=377449|name=Manganese(II) carbonate|accessdate=2014-05-06}}
| BoilingPt =
| RefractIndex = 1.597 (20 °C, 589 nm)
| MagSus = +11,400·10−6 cm3/mol
}}
|Section3={{Chembox Structure
| Coordination =
| CrystalStruct = hexagonal-rhombohedral
| Dipole =
}}
|Section4={{Chembox Thermochemistry
| HeatCapacity = 94.8 J/mol·K{{Cite web|url=http://chemister.ru/Database/properties-en.php?dbid=1&id=3854|title = Manganese(II) carbonate}}
| DeltaHc =
}}
|Section7={{Chembox Hazards
| ExternalSDS =
| MainHazards =
| FlashPt = Non-flammable
}}
|Section8={{Chembox Related
| OtherAnions =
| OtherCompounds =
}}
}}
Manganese carbonate is a compound with the chemical formula MnCO3. Manganese carbonate occurs naturally as the mineral rhodochrosite but it is typically produced industrially. It is a pale pink, water-insoluble solid. Approximately 20,000 metric tonnes were produced in 2005.{{cite encyclopedia|author=Arno H. Reidies|title=Manganese Compounds|encyclopedia=Ullmann's Encyclopedia of Industrial Chemistry|year=2007|publisher= Wiley-VCH|place=Weinheim|doi=10.1002/14356007.a16_123|isbn=978-3527306732}}
Structure and production
image:Calcium-carbonate-xtal-3D-SF.png. Color code: red = O, green = Mn.]]
MnCO3 adopts a structure like calcite, consisting of manganese(II) ions in an octahedral coordination geometry.{{cite journal|title=Structures of hydrothermally synthesized cobalt(II) carbonate and nickel(II) carbonate|author=Pertlik, F.|journal=Acta Crystallographica Section C|year=1986|volume=42|pages=4–5|doi=10.1107/S0108270186097524}}
Treatment of aqueous solutions of manganese(II) nitrate with ammonia and carbon dioxide leads to precipitation of this faintly pink solid. The side product, ammonium nitrate is used as fertilizer.
Image:Rhodochrosite-Pyrite-Calcite-219228.jpg, the mineral form of MnCO3, is of practical value as well as sought by collectors.]]
Reactions and uses
The carbonate is insoluble in water but, like most carbonates, hydrolyses upon treatment with acids to give water-soluble salts.
Manganese carbonate decomposes with release of carbon dioxide, i.e. calcining, at 200 °C to give MnO1.88:
:MnCO3 + 0.44 O2 → MnO1.88 + CO2
This method is sometimes employed in the production of manganese dioxide, which is used in dry-cell batteries and for ferrites.
Manganese carbonate is widely used as an additive within plant fertilizers. It is also used in multivitamins, in ceramics as a glaze colorant and flux, and in concrete stains.[http://www.stainedfloor.com/Manganese_Recipes.html "How To Stain Concrete with Manganese"]
Toxicity
Manganese poisoning, also known as manganism, may be caused by long-term exposure to manganese dust or fumes.
See also
References
{{reflist}}
{{carbonates}}
{{Manganese compounds}}