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.

the earth would become to overheated and everything alive on it will eventually die from overheating. plants will eventually die as well, water will evaporate, and it will be nothing but a hot planet without anything living on it.