Why should impure zinc be used instead of pure zinc in preparation of hydrogen gas

Explanation:

Pure zinc is not used for preparation of hydrogen gas because it is non-porous. As a result, the reaction carried out with pure zinc would be too slow. Hence, impurities like copper is often added to the zinc. Copper acts as a catalyst and increases the speed of the reaction.

answer; i believe the correct answer is (solid gold);

metals are good conductor of electricity. it has free electrons on their surface. according to electron pool theory, each atom present in a metal crystal losses all of its valence electron and as a result a pool of free is form. these pool of electrons are free to move and   conduct electricity easily   while making metal as good conductor.

the correct answer is a. the ability of electrons to flow throughout the metal.

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