Cobalt(II) acetate

Cobalt(II) acetate
Names
IUPAC name
Cobalt(II) acetate
Identifiers
71-48-7 (anhydrous) Yes
6147-53-1 (tetrahydrate) 
ChemSpider 6041 Yes
Jmol-3D images Image
PubChem 6277
UNII 3XC4P44U7E Yes
Properties
Co(C2H3O2)2
Molar mass 177.02124 g/mol (anhydrous)
249.08 g/mol (tetrahydrate)
Appearance Pink crystals (anhydrous)
intense red crystals (tetrahydrate)
Odor vinegar (tetrahydrate)
Density 1.705 g/cm3 (tetrahydrate)
Melting point 140 °C (284 °F; 413 K) (tetrahydrate)
Soluble
Solubility soluble in alcohol, dilute acids, pentyl acetate (tetrahydrate)
1.542 (tetrahydrate)
Hazards
MSDS J.T. Baker MSDS
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 1: Exposure would cause irritation but only minor residual injury. E.g., turpentine Reactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g., liquid nitrogen Special hazards (white): no codeNFPA 704 four-colored diamond
0
1
0
503 mg/kg (oral, rat)
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
  verify (what is: Yes/?)
Infobox references

Cobalt(II) acetate is the cobalt(II) salt of acetic acid. It is commonly found as the tetrahydrate Co(C2H3O2)2(H2O)4. It is used as an industrial catalyst.

Synthesis and structure

It may be formed by the reaction between cobalt oxide or hydroxide and acetic acid:

CoO + 2 HC2H3O2 + 3 H2O → Co(C2H3O2)2(H2O)4

The tetrahydrate has been shown by X-ray crystallography to adopt an octahedral structure, the central cobalt centre being coordinated by four water molecules and two acetate ligands.[1]

Reactions and uses

Cobalt acetate is a precursor to various oil drying agents, catalysts that allow paints and varnishes to harden.[2] Cobalt(II) acetate reacts with salenH2 to give salcomine, a transition metal dioxygen complex:[3]

Co(OAc)2 + salenH2 → Co(salen) + 2 HOAc

Safety

Cobalt salts are poisonous.[4]

References

  1. ↑ Van Niekerk, J. N.; Schoening, F. R. L. (1953). "The crystal structures of nickel acetate, Ni(CH3COO)2·4H2O, and cobalt acetate, Co(CH3COO)2·4H2O". Acta Cryst. 6 (7): 609–612. doi:10.1107/S0365110X5300171X.
  2. ↑ John Dallas Donaldson, Detmar Beyersmann, "Cobalt and Cobalt Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, Weinheim, 2005. doi:10.1002/14356007.a07_281.pub2
  3. ↑ Appleton, T. G. (1977). "Oxygen Uptake by a Cobalt(II) Complex". J. Chem. Ed. 54 (7): 443. doi:10.1021/ed054p443.
  4. ↑ MallBaker MSDS