Cu-->Cuo-->Cuso4-->Cu(OH)2
2 Cu + O2 = 2 CuO
CuO + H2SO4 = CuSO4 + H2O
CuSO4 + 2 NaOH = Cu(OH)2 + Na2SO4
2Cu+O2--->2CuO
CuO+SO3--->CuSO4
CuSO4+Ba (OH)2---> Cu(OH)2+Ba SO4