Question

When copper powder is heated, it gets coated with

• A. black copper oxide
• B. yellow copper oxide
• C. red copper oxide
• D. none of these

Answer 1

The correct option is A

black copper oxide

Explanation:

• The reaction corresponding to the gain of Oxygen (O) or loss of Hydrogen (H) by a species is called an oxidation reaction.
• Generally, metal undergoes reaction with oxygen molecule$\left({\mathrm{O}}_2\right)$ in the air to form metal oxide.
• When copper $\left(\mathrm{Cu}\right)$ is heated, it reacts with oxygen molecule $\left({\mathrm{O}}_2\right)$ in the air to form Copper(II) oxide$\left(\mathrm{CuO}\right)$. The Copper(II) oxide produced in the reaction is black in color.

$2\mathrm{Cu}\left(\mathrm{s}\right)+{\mathrm{O}}_2\left(\mathrm{g}\right)\to 2\mathrm{CuO}\left(\mathrm{s}\right)$

• Thus, when copper powder is heated, it gets coated with black copper oxide.

Final Answer:

Hence, the correct option is A.