Q306
Copper substances when exposed to air gains a green coating due to the formation of:
A.
CuO
B.
CuCO3 Cu(OH)2
AnswerC.
CuSO4
D.
Cu(NO3)2
Answer: Option B
Solution
Answer: Option B
Solution:
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.