Key Concepts: Redox Reactions

Core Definitions

• Oxidation: Loss of electrons (or gain of oxygen); oxidation number increases.
• Reduction: Gain of electrons (or loss of oxygen); oxidation number decreases.
• Redox Reaction: A reaction where oxidation and reduction occur simultaneously.
• Oxidizing Agent: The substance that is reduced (gains electrons); causes oxidation in another substance.
• Reducing Agent: The substance that is oxidized (loses electrons); causes reduction in another substance.
• OIL RIG: Memory aid: Oxidation Is Loss, Reduction Is Gain (of electrons).