Manganese(II) carbonate

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Manganese(II) carbonate
Impure sample of MnCO3
Identifiers
CAS number 598-62-9 YesY
PubChem 11726
ChemSpider 11233 YesY
UNII 9ZV57512ZM YesY
EC number 209-942-9
Jmol-3D images Image 1
Properties
Molecular formula MnCO3
Appearance White to faint pink solid
Density 3.12 g/cm3
Melting point 200–300 °C (392–572 °F; 473–573 K)
decomposes[1][2]
Solubility in water negligible
Solubility product, Ksp 2.24 x 10-11
Solubility soluble in dilute acid, CO2
insoluble in alcohol, ammonia
Refractive index (nD) 1.597 (20 °C, 589 nm)
Structure
Crystal structure hexagonal-rhombohedral
Thermochemistry
Specific
heat capacity
C
94.8 J/mol·K[2]
Std molar
entropy
So298
109.5 J/mol·K[2]
Std enthalpy of
formation
ΔfHo298
-881.7 kJ/mol[2]
Gibbs free energy ΔG -811.4 kJ/mol[2]
Hazards
EU Index Not listed
Flash point Non-flammable
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY (verify) (what is: YesY/N?)
Infobox references

Manganese carbonate is a compound with the chemical formula MnCO3. Manganese carbonate occurs naturally as the mineral rhodochrosite. Approximately 20,000 metric tonnes were produced in 2005.[3]

Production and uses[edit]

Treatment of aqueous solutions of manganese(II) salts with alkali metal carbonates leads to precipitation of this faintly pink solid. 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 at 200 °C to give manganese(II) oxide:

MnCO3 → MnO + CO2

This method is sometimes employed in the production of manganese dioxide for dry-cell batteries and for ferrites.[3]

Manganese carbonate is widely used as an additive to plant fertilizers to cure manganese deficient crops. It is also used in health foods, in ceramics as a glaze colorant and flux, and in concrete stains.[4]

It is used in medicine as a hematinic.

Toxicity[edit]

Manganese is essential for aerobic life and its compounds are not highly toxic.[citation needed] Manganese poisoning, also known as manganism, may be caused by long-term exposure to manganese dust or fumes.

See also[edit]

References[edit]

  1. ^ Sigma-Aldrich Co., Manganese(II) carbonate. Retrieved on 2014-05-06.
  2. ^ a b c d e http://chemister.ru/Database/properties-en.php?dbid=1&id=3854
  3. ^ a b Arno H. Reidies "Manganese Compounds" Ullmann's Encyclopedia of Chemical Technology 2007; John Wiley
  4. ^ "How To Stain Concrete with Manganese"
H2CO3 He
LiCO3 BeCO3 B C (NH4)2CO3,
NH4HCO3
O F Ne
Na2CO3,
NaHCO3,
Na3H(CO3)2
MgCO3,
Mg(HCO3)2
Al2(CO3)3 Si P S Cl Ar
K2CO3,
KHCO3
CaCO3,
Ca(HCO3)2
Sc Ti V Cr MnCO3 FeCO3 CoCO3 NiCO3 CuCO3 ZnCO3 Ga Ge As Se Br Kr
Rb2CO3 SrCO3 Y Zr Nb Mo Tc Ru Rh Pd Ag2CO3 CdCO3 In Sn Sb Te I Xe
Cs2CO3,
CsHCO3
BaCO3   Hf Ta W Re Os Ir Pt Au Hg Tl2CO3 PbCO3 (BiO)2CO3 Po At Rn
Fr Ra   Rf Db Sg Bh Hs Mt Ds Rg Cn Uut Fl Uup Lv Uus Uuo
La2(CO3)3 Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu
Ac Th Pa UO2CO3 Np Pu Am Cm Bk Cf Es Fm Md No Lr