Question:
If copper is kept open in air, it slowly loses its shining brown surface and gains a green coating. It is due to the formation of :
(a) CuSO4
(b) CUCO3CO(OH)2
(c) CU(NO3)2
(d) CuO.
Solution:
(b). The green coating is due to the formation of basic copper carbonate which is CuCO3.Cu(OH)2.