Reaction of Copper Oxide with Hydrogen

Problem This experiment demonstrates that it is possible to regain the red-brown copper from the black copper oxide with the help of hydrogen gas by 

Material Combustion pipe with stopper and exhaust pipe, porcelain boat, test tubes black copper oxide (wire form), hydrogen gas. 

Procedure Introduce hydrogen gas into the combustion pipe, which contains copper oxide filled in a porcelain boat. If the oxyhydrogen test turns out to be negative, light the hydrogen on the exhaust pipe and heat the copper oxide with a burner. As soon as the reaction sets in, indicated by the formation of metallic copper, remove the burner. Cool down the combustion pipe under a continuous hydrogen stream before the hydrogen supply is turned off. 

Observation Shiny red-brown metal is formed through the exothermic reaction copper. One can see clear drops of a liquid in the exhaust pipe water. 

Disposal The copper can be used for further experiments or it can be oxidized in a stream of air, enabling the copper oxide to be used again for the same experiment. 

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