Copper in copper mine is converted into soluble copper sulfate by sulfuric acid, and then iron is put into copper sulfate solution to replace copper. This method is called wet copper smelting. The technology of copper hydrometallurgy was invented by ancient people in China, and its principle is to make metal by displacement reaction. China is the first country in the world to adopt wet copper smelting.

Sodium carbonate is an inorganic compound with chemical formula NaCO and molecular weight of 105.99. It is also called soda ash, but it belongs to salt, not alkali. Another name is soda or soda ash. It is an important inorganic chemical raw material, which is mainly used to produce flat glass, glass products and ceramic glaze.