Chemistry
Assertion (A): Hydrogen and alkali metals react with a black copper oxide to give red/brown copper.
Reason (R): Hydrogen and alkali metals are good oxidising agents.
- Both A and R are true and R is the correct explanation of A.
- Both A and R are true but R is not the correct explanation of A.
- A is true but R is false.
- A is false but R is true.
Hydrogen
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Answer
A is true but R is false.
Explanation — Hydrogen and alkali metals react with copper oxide to give red/ brown copper.
CuO + H2 ⟶ Cu + H2O
CuO + 2Na ⟶ Cu + Na2O
Hence assertion (A) is true.
Both hydrogen and alkali metals acts as reducing agents. Hence reason (R) is False.
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Related Questions
The table given below shows the reaction of a few elements with acids and bases to evolve hydrogen gas.
Element Acid Base (A) X X (B) ✓ ✓ (C) ✓ X (D) ✓ ✓ Which of these elements will form amphoteric oxides.
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Reason (R): Hydrogen is slightly soluble in water.
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Reason (R): Granulated zinc contains traces of impurities which have a slight catalysing effect on the reaction.
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