\(CuO+2HCl\rightarrow CuCl_2+H_2O\)
\(CuCl_2+Ca\left(OH\right)_2\rightarrow Cu\left(OH\right)_2\downarrow+CaCl_2\)
\(Cu\left(OH\right)_2\rightarrow CuO+H_2O\)
\(CuO+H_2SO_4\rightarrow CuSO_4+H_2O\)
\((1)CuO+2HCl\to CuCl_2+H_2O\\ (2)CuCl_2+2NaOH\to Cu(OH)_2\downarrow+2NaCl\\ (3)Cu(OH)_2\xrightarrow{t^o}CuO+H_2O\\ (4)CuO+H_2SO_4\to CuSO_4+H_2O\)