Electrolysis of Melts

Part of the Oxidation and Reduction section of Coddy's Chemistry journey. Lesson 22 of 27.

Metals high in the series, such as aluminum, are made by electrolysis of their molten compounds.

Al³⁺ + 3e⁻ → Al

2O²⁻ → O₂ + 4e⁻

2Al₂O₃ → 4Al + 3O₂

Twelve electrons for every two Al₂O₃: a lot of electricity.

Challenge

In an aluminum smelter, aluminum oxide is split by electricity: Al₂O₃ → Al + O₂. Name the element reduced and count the electrons passed in the balanced equation.

Try it yourself

Oxidation numbersFollow the electrons

Al₂O₃AlO₂

Test yourself

This lesson includes a short quiz. Start the lesson to answer it and track your progress.

All lessons in Oxidation and Reduction

1Electron Transfer

What Is Oxidation Oxidation Numbers Rules for Oxidation Numbers Oxidation Numbers in Ions Recap - Number Painter

4Metals and Reactivity

The Reactivity Series Displacement Reactions Metals and Acids Corrosion and Rust Recap - Metal Contest

2Redox Reactions

Spotting Redox Oxidizing Agents Reducing Agents Electrons Passed Recap - Who Gave Electrons

5Electrochemistry

ElectrolysisElectrolysis of MeltsCells and Batteries Recap - Smelter

3Half-Equations

Writing Half-Equations Balancing with Electrons Half-Equations in Acid Combining Half-Equations Recap - Permanganate

6Practice Problems

Recap - Bleach and Iodide Recap - Copper and Silver Recap - Bromine Redox