GCSE CHEMISTRY - Copper - Purification by Electrolysis - Oxidation and Reduction

Extraction of Copper - Purification by Electrolysis.

Purification of Copper by Electrolysis

The anode is a block of impure copper.
The cathode is a thin piece of pure copper.

When electricity is passed through the cell
copper is dissolved at the anode by oxidation
and Cu²⁺ ions go into solution.

Cu_(s) - 2e^- Cu²⁺_(aq)

At the cathode, copper is deposited by reduction.

Cu²⁺_(aq) + 2e^- Cu_(s)

As copper ions move from the anode to the cathode
the anode gets smaller as the cathode gets bigger.
This is a redox reaction (continued).