ATAR Equilibrium Notes

Reversible Reaction

A chemical reaction where the reactants form products that can react to give the reactants back.

Dynamic Equilibrium

A state in which the reaction proceeds in both directions at the same rate, resulting in no net change.

Le Chatelier's Principle

When a system at equilibrium experiences stress, it will adjust to minimize the change and establish a new equilibrium.

Static Equilibrium

A condition where there is no exchange between reactants and products, and reactions have gone to completion.

Exothermic Reaction

A reaction that releases heat energy to the surroundings.

Endothermic Reaction

A reaction that absorbs heat energy from the surroundings.

Activation Energy (Ea)

The minimum energy required for a reaction to occur.

Collision Theory

States that particles only react if they collide with sufficient energy and the correct orientation.

Ksp (Solubility Product Constant)

The equilibrium constant for a sparingly soluble solid dissolving in water.

Common Ion Effect

The reduction of solubility of an ionic compound when a common ion is added to the solution.

Extent of Reaction

Describes how much product is formed when the system reaches equilibrium.

Homogeneous Equilibrium

An equilibrium where all substances are in the same phase, such as gases.

Heterogeneous Equilibrium

An equilibrium involving substances in different phases.

Entropy

A measure of molecular disorder in a system.

Dissociation

The process in which a compound separates into smaller particles, usually ions.

Equilibrium Expression

A mathematical representation showing the ratio of the concentrations of products and reactants at equilibrium.

Reaction Quotient (Q)

The ratio of products to reactants in any given state of a chemical reaction, used to determine the direction of a reaction.