Question

why has the black substances formed​

Answer 1

Answer:

This black substance formed on the surface is because of the process called surface oxidation. Upon heating, the copper metal melts gradually and turns black on the surface. This is because the copper powder present in the china dish reacts with the atmospheric oxygen and forms copper (II) oxide.

Explanation:

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Answer 2

Answer:

This black substance formed on the surface is because of the process called surface oxidation. Upon heating, the copper metal melts gradually and turns black on the surface. This is because the copper powder present in the china dish reacts with the atmospheric oxygen and forms copper (II) oxide.

Explanation:

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