A reddish brown coloured metal is used in electrical wires. When powdered and heated strongly in an open china dish, its colour turns black. When hydrogen gas is passed over this black substance, it regains its original colour. Based on the above information, answer the following question. (i) Name the metal and the black coloured substance formed. (ii) Write balanced chemical equations for both the reactions.

A reddish brown coloured metal is used in electrical wires. When powde

1.	A reddish brown coloured metal is used in electrical wires. When powdered and heated strongly in an open china dish, its colour turns black. When hydrogen gas is passed over this black substance, it regains its original colour. Based on the above information, answer the following question. (i) Name the metal and the black coloured substance formed. (ii) Write balanced chemical equations for both the reactions.
Answer» (i) The metal is copper and the black substance is copper (II) oxide or CuO. (ii) `2Cu + O_(2) overset("heat")rarr underset(("Black"))(2Cu(II)O)or 2CuO` `CuO + H_(2) overset ("heat")rarr Cu + H_(2)O`

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