Question

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Answer 1

Though coper is an less reactive metal but it reacts with atmospheric oxygen very slowly. Firstly it reacts with Cu to form Copper I oxide. With passage of time it further reacts with oxygen to form CopperII oxide. It is greenish in colour. Due to this corrosion it loses its shine and turns green.

Answer 2

Hey mate....

here's the answer....

Copper is not a high reactive metal but it also reacts with the oxygen present in atmosphere.

It reacts with oxygen and furthermore forms Copper oxide through which it loses its shine.

Hope this helps❤️