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Question
What is a redox reaction? Explain with an example.
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Solution
A redox reaction is a reaction in which oxidation and reduction reactions take place simultaneously.
When copper oxide is heated with hydrogen, then copper metal and water are formed:

In this reaction, CuO is changing into Cu. That is, oxygen is being removed from copper oxide. Oxygen is being added to hydrogen; H2 is changing into H2O. This shows that oxidation and reduction occur together.
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