What is Cobalt(II) oxide?
'''Cobalt(II) oxide''', also known as '''cobaltous oxide''', is a [[chemical compound]]. Its chemical formula is CoO. It contains [[cobalt]] in its +2 [[oxidation state]] as an [[ion]]. It also contains [[oxide]]. It can be green or red crystals. It can also be a grey or brown powder. ==Preparation== [[Cobalt(II) chloride]] reacts with a [[base (chemistry)|base]] to get [[cobalt(II) hydroxide]]. Then the cobalt(II) hydroxide is heated to make cobalt(II) oxide. The reactions are written below: : CoCl<sub>2</sub> + 2 NaOH → 2 NaCl + Co(OH)<sub>2</sub> : Co(OH)<sub>2</sub> → CoO + H2O ==Use== It can react with [[acid]]s to make [[salt]]s containing cobalt. It is used to make blue glass. ==Related pages== *[[Cobalt(II) sulfate]] *[[Cobalt(III) oxide]] [[Category:Cobalt compounds]] [[Category:Oxides]] {{chem-stub}}