COBALT OXALATECobalt oxide are oxides of Cobalt and are Inorganic Compounds. There are three oxides of cobalt.

They are as below,
1) Cobalt (II) oxide known as Cobaltous Oxide or Cobalt monoxide.
2) Cobalt (III) oxide known as Cobaltic oxide or Di cobalt trioxide.
3) Cobalt (II, III) oxide known as Cobaltosic oxide, Tri Cobalt tetroxide, Cobalto-cobaltic oxide.
Cobalt (II) oxide CAS number [1307-96-6] has Molecular formula CoO, Mol. Wt.: 74.9326 gm. /mole. It is a blackish or grayish powder finds its application mainly in ceramic industries and also in chemical industries for preparing Cobalt (II) salts such as Cobalt (II) nitrate having Mol. Formula Co( NO3 )2.
Cobalt (III) oxide CAS number [1308-04-9] has Molecular formula Co2 O3, Mol. Wt.: 165.86 gm. / mole. It is a black colored powder.
Cobalt (II, III) oxide CAS number [1308-06-1] has Molecular formula Co3 O4, Molecular Wt.: 240.8 gm. /mole. It is available in black colored powder form, soluble in hot acids and alkali hydroxides. Cobalt (II, III) oxide is used mainly as a pigment in glass industries.

Cobalt oxide is an olive-green to red crystals, or grayish or black powder in appearance, cobalt oxide is used extensively in the ceramics industry as an additive to create blue colored glazes and names as well as in the chemical industry for producing cobalt (II) salts.

Cobalt oxide is a metallic pigment that provides blue coloring in porcelains and glass. Various forms of cobalt oxide are changes to CoO at 850 – 900 C. CoO is a grayish brown powder that decomposes at 1935 C, insoluble in water. It is also used as a drying agent in inks and varnishes and as a feed and fertilizer additive.