Cobalt(II) oxide

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Template:Chembox header | Cobalt(II) oxide
Cobalt(II) oxide
Template:Chembox header | General
Systematic name Cobalt(II) Oxide
Other names Cobaltous Oxide,
Cobalt Monoxide,
Cobaltous Monoxide
Molecular formula CoO
Molar mass 74.93 g/mol
Appearance A black powder
CAS number 1307-96-6
Template:Chembox header | Properties
Density and phase 6.1 g/cm3
Solubility in water practically insoluble in water,
soluble in strong acids
Melting point 1933°C (2206 K)
Boiling point ?°C (? K)
Template:Chembox header | Hazards
MSDS (Use CAS#) Fisher Scientific
Main hazards Respiratory tract inflammation
possibly carcinogenic
NFPA 704 Template:NFPA 704
R/S statement R: 22 43 50-53 S: (2-)24-37-60-61
RTECS number GG2800000
Template:Chembox header | Related compounds
Other anions Cobalt(II) carbonate
Cobalt(II) nitrate, Cobalt(II) chloride
Other cations Iron(III) oxide, Iron(II) oxide
Cobalt(II,III) oxide
Related compounds Cobalt(III) oxide
Template:Chembox header | Except where noted otherwise, data are given for
materials in their standard state (at 25°C, 100 kPa)
Infobox disclaimer and references


Cobalt(II) oxide is a blackish gray powder used extensively in the ceramics industry as an additive to create blue colored glazes and enamels as well as in the chemical production industry for producing cobalt(II) salts.

Cobalt(II) oxide is a product of Cobalt(II,III) oxide decomposing at 895 °C through the reaction:

2 Co3O4(s) → 6 CoO(s) + O2(g)

Cobalt(II) oxide is also a product of Cobalt(II) carbonate decomposing through the reaction:

CoCO3(s) → CoO(s) + CO2(g)

Ceramics

Cobalt(II) Oxide has been used for centuries as a coloring agent on kiln fired ceramic glazes, the earliest examples go back to the beginnings of kiln fired pottery. Cobalt(II) Oxide colorants are stable and retain their coloration indefinitely. The oxide is one of the most powerful colorants commonly used in the making of glazes and slips and requires only 1 part oxide to 100,000 parts glazing compound to produce the deep blue shade commonly referred to as cobalt blue. By varying the temperature of the kiln, the potter can adjust the coloring of the oxide ranging anywhere from the familiar blue, to a shade nearing black. [1]

Industrial Uses

As stated earlier, cobalt(II) oxide is used in the production of cobalt(II) salts such as CoCl2 and Co(NO3)2. Cobalt(II) oxide can also be found in animal feed and fertilizer as a supplement to aid in the production of Vitamin B12.

Health Concerns

References

  1. Zamek, Jeff: "A Problem With Cobalt?" Ceramics Today http://www.ceramicstoday.com/articles/zamek_cobalt.htm