Question
What happens when hydrogen gas is added to copper oxide?
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Answer
If hydrogen gas is passed over heated copper oxide (CuO), the black coating on the surface turns brown as the reverse reaction takes place and copper is obtained. The chemical reaction is as follows:$\text{CuO}+\text{H}_2\rightarrow\text{Cu}+\text{H}_2\text{O}$
The second reaction is called oxidation-reduction reaction or redox reaction. As during this reaction the copper(II) oxide is losing oxygen and is being reduced. The hydrogen is gaining oxygen and is being oxidised.In other words, one reactant gets oxidised while the other gets reduced.
The second reaction is called oxidation-reduction reaction or redox reaction. As during this reaction the copper(II) oxide is losing oxygen and is being reduced. The hydrogen is gaining oxygen and is being oxidised.In other words, one reactant gets oxidised while the other gets reduced.
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