Cobalt(II) carbonate

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Cobalt(II) carbonate
Co2+ CO32−
Cobalt(II) carbonate powder
Cobalt(II) carbonate powder
Names
IUPAC name
Cobalt(II) carbonate
Other names
Cobaltous carbonate; cobalt(II) salt
Identifiers
3D model (
JSmol
)
ChemSpider
ECHA InfoCard
 100.007.428 Edit this at Wikidata
UNII
  • InChI=1S/CH2O3.Co/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2 ☒N
    Key: ZOTKGJBKKKVBJZ-UHFFFAOYSA-L ☒N
  • InChI=1/CH2O3.Co/c2-1(3)4;/h(H2,2,3,4);/q;+2/p-2
    Key: ZOTKGJBKKKVBJZ-NUQVWONBAB
SMILES
  • C(=O)([O-])[O-].[Co+2]
Properties
CoCO3
Molar mass 118.941 g/mol
Appearance pink solid
Density 4.13 g/cm3
Melting point 427 °C (801 °F; 700 K) [3]
decomposes before melting to cobalt(II) oxide (anhydrous)
140 °C (284 °F; 413 K)
decomposes (hexahydrate)
0.000142 g/100 mL (20 °C)[1]
1.0·10−10[2]
Solubility soluble in acid
negligible in alcohol, methyl acetate
insoluble in ethanol
1.855
Structure
Rhombohedral (anhydrous)
Trigonal (hexahydrate)
Thermochemistry
79.9 J/mol·K[3]
Std enthalpy of
formation
(ΔfH⦵298)
 −722.6 kJ/mol[3]
−651 kJ/mol[3]
Hazards
GHS labelling:
GHS07: Exclamation markGHS08: Health hazard[4]
Warning
H302, H315, H317, H319, H335, H351[4]
P261, P280, P305+P351+P338[4]
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
0
0
Lethal dose or concentration (LD, LC):
640 mg/kg (oral, rats)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
☒N verify (what is checkY☒N ?)

Cobalt(II) carbonate is the

catalysts.[5] Cobalt(II) carbonate also occurs as the rare red/pink mineral spherocobaltite.[6]

Preparation and structure

Structure of solid cobalt(II) carbonate shown with space-filling ions. Color code: red = O, green = Co, blck = C

It is prepared by combining solutions of

cobalt(II) sulfate and sodium bicarbonate
:

CoSO4 + 2 NaHCO3 → CoCO3 + Na2SO4 + H2O + CO2

This reaction is used in the precipitation of cobalt from an extract of its roasted ores.[5]

CoCO3 adopts a structure like

octahedral coordination geometry.[7]

Reactions

Like most transition metal carbonates, cobalt carbonate is insoluble in water, but is readily attacked by mineral acids:

CoCO3 + 2 HCl + 5 H2O → [Co(H2O)6]Cl2 + CO2

It is used to prepare many coordination complexes. The reaction of cobalt(II) carbonate and acetylacetone in the presence of hydrogen peroxide gives tris(acetylacetonato)cobalt(III).[8]

Heating the carbonate proceeds in a typical way for

calcining
, except that the product becomes partially oxidized:

6 CoCO3 + O2 → 2 Co3O4 + 6 CO2

The resulting

CoO at high temperatures.[9]

Uses

Cobalt carbonate is a precursor to

essential element. It is a precursor to blue pottery glazes, famously in the case of Delftware
.

At least two cobalt(II) carbonate-hydroxides are known: Co2(CO3)(OH)2 and Co6(CO3)2(OH)8·H2O.[10]

The moderately rare

Republic of Congo. "Cobaltocalcite" is a cobaltiferous calcite variety that is quite similar in habit to spherocobaltite.[6]

carbonate ligands
.

Safety

Toxicity has rarely been observed. Animals, including humans, require trace amounts of cobalt, a component of vitamin B12.[5]

References

  1. ISBN 978-1-4987-5429-3
    .
  2. ^ "Solubility product constants". Archived from the original on 2012-06-15. Retrieved 2012-05-17.
  3. ^ a b c d "Cobalt(II) carbonate".
  4. ^ a b c Sigma-Aldrich Co., Cobalt(II) carbonate. Retrieved on 2014-05-06.
  5. ^
    ISBN 3527306730
    .
  6. ^ a b "Spherocobaltite: Spherocobaltite mineral information and data". www.mindat.org. Retrieved 7 August 2018.
  7. doi:10.1107/S0108270186097524
    .
  8. ISBN 9780470132364. {{cite book}}: ISBN / Date incompatibility (help
    )
  9. doi:10.1007/BF01980784
    .
  10. S2CID 58657483
    .
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