Electrolysis — Principles

This lesson covers the fundamental principles of electrolysis for Edexcel GCSE Chemistry (1CH0). You need to understand what electrolysis is, know the key terminology, explain how ions move during electrolysis, and identify oxidation and reduction at each electrode.

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What Is Electrolysis?

Electrolysis is the process of using electricity to decompose (break down) an ionic compound that is either molten (melted) or dissolved in water (aqueous).

The word "electrolysis" comes from the Greek:

• Electro = electricity
• Lysis = splitting/breaking down

Key Definition

Electrolysis is the decomposition of an electrolyte using a direct current (d.c.) of electricity.

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Key Terminology