Simplify the following text for a Grade 7 native English-speaking person.
Original: A laboratory method for preparing copper ( II ) oxide is to electrolyze water containing sodium bicarbonate at a moderate voltage with a copper anode , collect the mixture of copper hydroxide , basic copper carbonate , and copper carbonate produced , and heat it .
Simplified: It can also be made by heating copper ( II ) carbonate or copper ( II ) nitrate .