Reduction and Oxidation

Reduction and Oxidation

Fundamental Definitions

• Oxidation refers to the loss of electrons from an atom, ion, or molecule.
• Reduction involves the gain of electrons by an atom, ion, or molecule.

Changes During Oxidation & Reduction

• Throughout an oxidation reaction, a substance loses electrons and its oxidation number increases.
• During a reduction reaction, a substance gains electrons and its oxidation number decreases.

Oxidising and Reducing Agents

• An oxidising agent is a substance that accepts electrons from another substance, causing it to oxidise while itself being reduced.
• A reducing agent is a substance that donates electrons to another substance, causing it to reduce while itself being oxidised.

Redox Reactions

• A reaction that involves both oxidation and reduction simultaneously is known as a redox reaction.

Observing Oxidation & Reduction in Chemical Equations

• In a balanced chemical equation, the total increase in oxidation numbers of oxidised atoms is equal to the total decrease in oxidation numbers of reduced atoms.
• Electrons appear on different sides of the equation for oxidation and reduction: for oxidation, electrons are on the products (right) side; for reduction, electrons are on the reactants (left) side.

Applications of Redox Reactions

• Redox reactions are fundamental to processes like corrosion and the functioning of batteries.
• In metallurgy, many metals are extracted from their ores using redox reactions.

Remember, OIL RIG: Oxidation Is Loss, Reduction Is Gain (referring to electrons).