Equillibrium

Definition: A state in a reversible reaction where the rates of the forward and reverse reactions are equal, so concentrations of reactants and products remain constant.

Constant Concentrations: Not equal, but steady over time.

Ongoing Reactions: Both forward and reverse reactions occur continuously.

Acids: Proton donors (H⁺)

Bases: Proton acceptors (H⁺)

Strong Acids/Bases: Completely dissociate in water (high Kₐ or K_b).

Weak Acids/Bases: Partially dissociate (low Kₐ or K_b).

Dynamic Equilibrium: In weak acids/bases, equilibrium is established between the acid/base and its conjugate base/acid.

Biological Systems: Enzyme-catalyzed reactions, pH regulation in blood.

Biochemical Systems: Metabolic pathways, drug interactions.

Technological Systems: Industrial synthesis (e.g., Haber process), pollution control, manufacturing processes.

K = [Products]/[Reactants]

Using K: Solve for unknown concentrations or equilibrium positions.

ICE Tables: Initial, Change, Equilibrium approach for solving equilibrium problems.

Principle: If a system at equilibrium is disturbed by changing conditions, the system will adjust to counteract the disturbance and restore a new equilibrium.

Concentration: Adding/removing reactants or products shifts the equilibrium.

Temperature: Changing temperature affects the equilibrium position depending on whether the reaction is exothermic or endothermic.

Pressure: For gaseous reactions, increasing pressure shifts equilibrium towards the side with fewer moles of gas.

Catalysts: Affect the rate of reaching equilibrium but not the position of equilibrium.