Question

A reddish brown powdered heated strongly in China dish its colour turn black. When hydrogen gas is passed over this back substance it regains its original colour. (i) Name the metal and black coloured substance. (ii) Write the balanced chemical reaction for both​

Answer 1

Explanation:

1. Copper powder is reddish brown powder and when heated strongly it turns to copper oxide.
2.    2 Cu (s) + O2 (g) ---> 2 CuO (s) (when copper powder heated) CuO (s) + H2 (g) ---> Cu (s) + H2O (g) (When the hydrogen is passed through the black powder)