Carbon can be used to extract copper oxide because it acts as a reducing agent. Here's how it works:

* Copper oxide (CuO) is a metal oxide, and it is relatively stable.

* Carbon (C) is a good reducing agent because it readily reacts with oxygen.

* When heated together, carbon reacts with the oxygen in copper oxide, forming carbon dioxide (CO2). This leaves behind pure copper metal.

Here's the chemical equation:

2CuO + C → 2Cu + CO2

In summary:

* Carbon's high affinity for oxygen allows it to pull oxygen away from copper oxide.

* This process reduces the copper oxide, leaving pure copper metal behind.

Practical applications:

This process is used in the metallurgical industry to extract copper from its ores. The reaction is typically carried out in a furnace at high temperatures.