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Karnataka Board PUCPUC Science Class 11

Justify that the following reaction is redox reaction: CuO(s)+HX2(g)⟶Cu(s)+HX2O(g)

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Question

Justify that the following reaction is redox reaction:

\[\ce{CuO(s) + H2(g) → Cu(s) + H2O(g)}\]

Numerical
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Solution

\[\ce{CuO(s) + H2(g) → Cu(s) + H2O(g)}\]

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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Chapter 7: Redox Reactions - EXERCISES [Page 280]

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NCERT Chemistry Part 1 and 2 [English] Class 11
Chapter 7 Redox Reactions
EXERCISES | Q 8.3 - (a) | Page 280

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