Question

.A reddish brown coloured metal used in electric wires, when powdered and heated strongly in an open Chinadish, its colour turns black. When hydrogen gas is passed over this black substances, it regain its original colour. Based on this information, the metal and black coloured substances are

Answer 1

Answer:

(i) The brown colour metal is copper (Cu) . And it's black colour oxide is Copper Oxide .

ii) Case 1)

Cu + O2 ----> CuO

Case 2)

CuO + H2 ------> Cu + H2O