some metals, for example: Cu, Au, Pb, Zn, Fe, etc. are capable to have chemical reactions in serie.
In this case, the (Cu), can be transformed to Nitrate, Carbonate, sulfate and metallic copper.
In presence of (HNO3) the copper is transformed to Cupric nitrate.
Cu + HNO3 ———— ) Cu(NO3)2
By adding (NaHCO3) in satured solution and with high temperature we can observe a greenish color. (Cupric Carbonate)
Cu(NO3)2 + NaHCO3 ———— ) CuCO3 + NaNO3 + H2
By adding Sulfuric acid, we can synthesize Copper sulphate
CuCO3 + H2SO4 ———— ) CuSO4 + H2O + CO2
Finally we obtain the pure copper, with a shift reaction through the addition of the Zn, that has more affinity with the sulfate than the Copper.
CuSO4 + Zn ———— ) ZnSO4 + Cu