Definition - What does Oxidized Copper mean?
Oxidation, in the case of copper, is a type of corrosion. It is a three-step process where copper oxidizes to copper oxide, then to cuprous or cupric sulfide and finally to copper carbonate. It results in a green-colored copper or patina that forms over time.
Corrosionpedia explains Oxidized Copper
Copper, when exposed to the atmosphere, will become oxidized due to a reaction with oxygen. The reaction takes place when water or moisture in the air comes into contact with copper.
The basic reaction of copper with the oxygen in the atmosphere, which converts copper to copper oxide is as follows:
2 Cu(s) + O2 (g) --> 2 CuO(s)
This conversion of copper to patina is a multiple-step process, and it takes long time to form copper carbonate. Here is the list of oxides which form during the oxidation process of copper to patina.
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