Hall

Definition

Charles Martin Hall was an American chemist who co-discovered the Hall-Héroult process for aluminum extraction. This process revolutionized the production of aluminum by significantly reducing its cost.

5 Must Know Facts For Your Next Test

1. The Hall-Héroult process is the primary industrial method for extracting aluminum from bauxite ore.
2. Hall discovered his method in 1886, independently but simultaneously with French engineer Paul Héroult.
3. The Hall-Héroult process involves dissolving alumina ($Al_2O_3$) in molten cryolite ($Na_3AlF_6$) and then electrolyzing the solution to produce pure aluminum.
4. This process requires a significant amount of electrical energy, which is why aluminum production is often located near cheap and abundant electricity sources.
5. Before the Hall-Héroult process, aluminum was considered a precious metal more expensive than gold due to its difficulty to extract.

Review Questions

• What is the main industrial method used for extracting aluminum?
• Who co-discovered the process that revolutionized aluminum production?
• What role does cryolite play in the Hall-Héroult process?

Related terms

Bauxite: The primary ore from which aluminum is extracted. It consists mainly of hydrated alumina minerals.

Cryolite: $Na_3AlF_6$, a mineral used as a solvent in the electrolytic production of aluminum in the Hall-Héroult process.

Electrolysis: $\text{A chemical process that uses electric current to drive a non-spontaneous reaction.}$