Question

cu=cuo=cucl2=cu(oh)2=cuo=cu

Answer 1

1. 2Cu+O2=2CuO
2. CuO+2HCl=CuCl2+H2O
3. CuCl2+2NaOH=Cu(OH)2+2NaCl
4. Cu(OH)2=CuO+H2O(Пр нагревании)
5. CuO+H2=Cu+H2O