Question

Which element is oxidized in the following reaction: CuO(s) + H2 (g) Cu(s) + H2O (l)

Answer 1

Oxide + hydrogen is the element that is oxidized.

Answer 2

Answer :  The oxidized element is, hydrogen.

Explanation :

Redox reaction or Oxidation-reduction reaction : It is defined as the reaction in which the oxidation and reduction reaction takes place simultaneously.

Oxidation reaction : It is defined as the reaction in which a substance looses its electrons. In this, oxidation state of an element increases. Or we can say that in oxidation, the loss of electrons takes place.

Reduction reaction : It is defined as the reaction in which a substance gains electrons. In this, oxidation state of an element decreases. Or we can say that in reduction, the gain of electrons takes place.

The balanced redox reaction is :

$CuO(s)+H_2(g)\rightarrow Cu(s)+H_2O(l)$

The half oxidation-reduction reactions are:  

Oxidation reaction : $H_2\rightarrow 2H^++2e^-$

Reduction reaction : $Cu^{2+}+2e^-\rightarrow Cu$

In this reaction, the oxidation state of 'H' changes from (0) to (+1) that means 'H' lost 1 electron and it shows oxidation reaction and the oxidation state of 'Cu' changes from (+2) to (0) that means 'Cu' gain 1 electron and it shows reduction reaction.

Thus, 'H' is oxidized and 'Cu' is reduced.