Question

notice about cricket quize in our school so the head boy is write that notice for the notice board that mentioning the day , date and the time of quize​

Answer 1

Explanation:

oxide formed is black in colour. The black colour is formed due to the oxidation of copper takes place. (b) When hydrogen gas is passed over hot copper oxide, the black coating on the surface turns brown as the reverse reaction takes place and copper is obtained.