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प्रश्न
Justify that the following reaction is redox reaction:
\[\ce{CuO(s) + H2(g) → Cu(s) + H2O(g)}\]
उत्तर
\[\ce{CuO(s) + H2(g) → Cu(s) + H2O(g)}\]
Let us write the oxidation number of each element involved in the given reaction as:
\[\ce{^{+2}Cu^{-2}O(s) + ^0H2(g) → ^0Cu(s) + ^{+1}H2^{-2}O(g)}\]
Here, the oxidation number of Cu decreases from +2 in CuO to 0 in Cu i.e., CuO is reduced to Cu. Also, the oxidation number of H increases from 0 in H2 to +1 in H2O i.e., H2 is oxidized to H2O. Hence, this reaction is a redox reaction.
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