Question

When the powder of common metal is heated in open china dish, its colour turns black. However, when hydrogen is passed over the hot black substance so formed, it regains its original colour. Based on the above information answer the following questions:
i. What type of chemical reaction takes place in each of the two given steps?
ii. Name the metal initially taken in the powder form. Write balanced chemical equations for both reactions.

Answer 1

i. In the first step, oxidation takes place and in the second step, redox reaction takes place.
ii. The metal initially taken in powder form was copper.