Copper substances when exposed to air gains a green coating due to the formation of: (1) CuO (2) CuCO3 Cu(OH)2 (3) CuSO4 (4) Cu(NO3)2

1 Answer

Answer :

(2) CuCO3 Cu(OH)2 Explanation: When copper is exposed to air, it reacts with moist carbon dioxide in the air and slowly loses its shiny brown surface and gains a green coat. This green substance is basic copper carbonate (CuCO3 Cu(OH)2). The formation of this green coating on the surface of a copper object corrodes it.

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