Question

what hapeen when copeer is heated in air​

Answer 1

Explanation:

Heated copper metal reacts with oxygen to form the black copper oxide. The copper oxide can then react with the hydrogen gas to form the copper metal and water. When the funnel is removed from the hydrogen stream, the copper was still be warm enough to be oxidized by the air again.

Answer 2

Answer:

it turns Brown in colour due to oxidation to copper oxide.