Question

Why does copper gets a black colour coating on burning?

Answer 1

Answer:

Because, when it is heated then there is a reaction with the oxygen and this reaction became a black. The color of the heated copper powder becomes black when air is passed over it because of its reaction with oxygen i.e. air. When it reacts with oxygen it forms copper oxide which is black in color.

Answer 2

coupper get a black colour coating on burning because it get oxidised with oxygen present in atmosphere which changes its colour to become black .The thin film is its oxidised layer which saves its internal part .