Cobalt(II) Oxide
Get Cobalt II Oxide essential facts below. View Videos or join the Cobalt II Oxide discussion. Add Cobalt II Oxide to your topic list for future reference or share this resource on social media.
Cobalt II Oxide
Cobalt(II) oxide
Cobalt(II) oxide
IUPAC name
Cobalt(II) oxide
Other names
Cobaltous oxide
Cobalt monoxide
3D model (JSmol)
ECHA InfoCard 100.013.777 Edit this at Wikidata
EC Number
  • 215-154-6
RTECS number
  • GG2800000
UN number 3288
Molar mass 74.9326 g/mol
Appearance olive orr gray powder
Odor odorless
Density 6.45 g/cm3[1]
Melting point 1,933 °C (3,511 °F; 2,206 K)
insoluble in water[2]
+4900.0·10-6 cm3/mol
cubic, cF8
Fm3m, No. 225
Safety data sheet ICSC 1551
GHS pictograms GHS07: HarmfulGHS09: Environmental hazard
GHS Signal word Warning
H302, H317, H400, H410
P260, P280, P284, P301+310+330, P304+340+310, P342+311, P403+233
NFPA 704 (fire diamond)
Flammability code 0: Will not burn. E.g. waterHealth code 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasReactivity code 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no codeNFPA 704 four-colored diamond
Flash point Non-flammable
Lethal dose or concentration (LD, LC):
202 mg/kg
Related compounds
Other anions
Cobalt(II) sulfide
Cobalt(II) hydroxide
Other cations
Iron(II) oxide
Nickel(II) oxide
Related compounds
Cobalt(II,III) oxide
Cobalt(III) oxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY?N ?)
Infobox references

Cobalt(II) oxide is an inorganic compound that has been described as an olive-green[3] or gray[4] solid. It is used extensively in the ceramics industry as an additive to create blue colored glazes and enamels as well as in the chemical industry for producing cobalt(II) salts. A related material is cobalt(II,III) oxide, a black solid with the formula Co3O4.

Structure and properties

CoO crystals adopt the periclase (rock salt) structure with a lattice constant of 4.2615 Å.[5]

It is antiferromagnetic below 16 °C.[6]


Cobalt(II) oxide is prepared by oxidation of cobalt powder with air or by thermal decomposition of cobalt(II) nitrate or the carbonate.[3][4]

Cobalt(II,III) oxide decomposes to cobalt(II) oxide at 950 °C:[7]

2 Co3O4 -> 6 CoO + O2

It may also be prepared by precipitating the hydroxide, followed by thermal dehydration:

CoX2 + 2 KOH -> Co(OH)2 + 2 KX
Co(OH)2 -> CoO + H2O


As can be expected, cobalt(II) oxide reacts with mineral acids to form the corresponding cobalt salts:

CoO + 2 HX -> CoX2 + H2O


Cobalt(II) oxide has for centuries used as a coloring agent on kiln fired pottery. The additive provides a deep shade of blue named cobalt blue. The band gap (CoO) is around 2.4 eV.[] It also is used in cobalt blue glass.

See also


  1. ^ Lide, David R., ed. (2006). CRC Handbook of Chemistry and Physics (87th ed.). Boca Raton, FL: CRC Press. ISBN 0-8493-0487-3.
  2. ^ Advanced Search - Alfa Aesar - A Johnson Matthey Company Archived 2011-07-19 at the Wayback Machine. Retrieved on 2011-11-19.
  3. ^ a b Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.
  4. ^ a b Donaldson, John Dallas; Beyersmann, Detmar (2005). "Cobalt and Cobalt Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a07_281.pub2.
  5. ^ Kannan, R.; Seehra, Mohindar S. (1987). "Percolation effects and magnetic properties of the randomly diluted fcc system CopMg1-pO". Physical Review B. 35 (13): 6847-6853. doi:10.1103/PhysRevB.35.6847.
  6. ^ Silinsky, P. S.; Seehra, Mohindar S. (1981). "Principal magnetic susceptibilities and uniaxial stress experiments in CoO". Physical Review B. 24: 419-423. doi:10.1103/PhysRevB.24.419.
  7. ^ US 4389339, James, Leonard E.; Crescentini, Lamberto & Fisher, William B., "Process for making a cobalt oxide catalyst" 

  This article uses material from the Wikipedia page available here. It is released under the Creative Commons Attribution-Share-Alike License 3.0.



Music Scenes