Copper substances when exposed to air gains a green coating due to the formation of:

A CuO<br>
B CuCO<sub>3</sub> Cu(OH)<sub>2</sub>
C CuSO<sub>4</sub>
D Cu(NO<sub>3</sub>)<sub>2</sub>

Correct Answer: CuCO<sub>3</sub> Cu(OH)<sub>2</sub>

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.
Bissoy MCQ
#General Knowledge #Chemistry

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