Question

Cu → CuO → Cu(NO3)2 → Cu(OH)2 → CuCl2 → Cu(OH)2 → CuSO4 → Cu

Answer 1

2Cu+O2=2CuO

CuO+2HNO3=Cu(NO3)2+H2O

Cu(NO3)2+2NaOH=2NaNO3+Cu(OH)2

Cu(OH)2+2HCl=CuCl2+2H2O

CuCl2+2NaOH=2NaCl+Cu(OH)2

Cu(OH)2+H2SO4 =СuSO4+2H2O

CuSO4+Ag=AgSO4+Cu