chemicals
copper is an element, you cant make copper
Sulphuric acid is mixed with copper oxide to make copper sulphate through a chemical reaction.
copper and tin make bronze
Yellow, red and slight bit of blue make copper.
Sulfuric acid is commonly used to make copper sulfate by reacting it with copper oxide or copper carbonate. The reaction forms copper sulfate and water, with sulfuric acid providing the necessary protons for the reaction.
you can make copper stuff
Sodium hydroxide is commonly used to make copper sulfate from copper oxide, which is insoluble in water. The reaction between copper oxide and sodium hydroxide forms copper sulfate and water.
To make copper turn green, you can expose it to air and moisture over time. This process, called oxidation, forms a greenish layer of copper carbonate on the surface of the copper.
Brass is mainly an alloy of copper and zinc. Some alloys do have small amounts of arsenic added also.
Zinc and copper make brass, and tin and copper make bronze.
Copper is an element in and of itself - you can't "mix" any other substances to get it. Copper is mixed with zinc to make brass, or with tin to make bronze.
Hammered copper can be used in many decorative or useful items. The effect of hammering the copper is to make a dented effect all over the copper. This can catch the light and make an attractive surface.