Describe the Process of Electrolysis in the Production of Metals

Aluminum can be extracted from ore through electrolysis.
••• Digital Vision./Digital Vision/Getty Images

Electrolysis is the process of using electric current to induce a chemical reaction. The chemical reaction in question is typically a reduction-oxidation reaction, wherein atoms exchange electrons and change oxidation states. This process can be used to produce metal solids, which is useful for electroplating and the purification of various metals.

Basic Setup of Electrolysis

Electrolysis requires two oppositely charged poles, called the cathode and anode. The cathode is negatively charged; it is the site of the reduction of positive ions. The anode is positively charged; it is the site of the oxidation of negative ions. In an electrolytic cell, these two poles are connected to an external power source. The circuit is typically completed by a salt solution called the electrolyte. In the production of metal through electrolysis, a layer of metal will form on the cathode.

The Nature of the Reaction

In a reduction-oxidation -- or redox -- reaction, two different elements exchange electrons. In the process of electrolysis, solid or molten metal will appear when a positively charged metal ion gains electrons such that it has a neutral charge. The positive metal ions are present in the electrolytic solution. They can form a solid or molten metal on the cathode when electrical current is applied to the apparatus. For example, in the electrolytic purification of aluminum, aluminum ions from the electrolyte will be reduced at a cathode, forming very pure aluminum.

The Application of Electricity

In order for the production of metal to take place, an electrical potential must be applied. In the process of electrolysis, this flow of electrons typically comes from an external DC current. Once the electrical current is applied, electrons will move through the external circuit, and positive ions will move in the electrolyte. Then the cathode can undergo reduction with these electrons and ions to form metal.

The End Point of Electroplating

The electroplating process is limited by the amount of positive metal ions in the electrolytic solution. Once all these ions have been used up, the reaction will have no way of continuing. Hence, no more metal will form. In order to continue forming more metal, you must add more positive metal ions to the electrolytic solution.

Related Articles

Why Does Citric Acid Produce Electricity?
The Effect of pH in Electroplating
Chemicals Used in Gold Plating
Gold Smelting Process
Methods of Plating Stainless Steel
How to Write the Net Ionic Equation for the Reaction...
Do Metal Atoms Lose Their Valence Electrons When Forming...
Science Facts About Magnets for Kids
Alodine Vs. Anodizing
How to Galvanize Metal
Bronze Plating Process
How Do Batteries Work? Parts, Types & Terminology (w/...
What Causes a Nail to Rust?
DIY Electroplating
What Happens to the Oxidation Number When an Atom in...
What Is Output Voltage?
The Uses for Electroplating
List of Positive & Negative Ions
Why Do Batteries Go Flat?
How to Determine Conductivity in Compounds

Dont Go!

We Have More Great Sciencing Articles!