AP®︎ Chemistry: Topic 7.9 Flashcards

A system at equilibrium shifts to oppose an imposed change and reestablish equilibrium.

Forward and reverse reactions occur at equal rates, so concentrations remain constant.

An external change such as concentration, temperature, pressure, volume, or dilution disturbance.

Adding a species shifts away from it; removing one shifts toward it.

If another reaction consumes a component, equilibrium shifts to replace the removed substance.

Increasing temperature favors the endothermic direction; decreasing temperature favors the exothermic direction.

In endothermic reactions heat acts like a reactant; in exothermic reactions it acts like a product.

Adding a nonreactive gas at constant volume does not change equilibrium position.

Adding solvent lowers concentrations, shifting equilibrium toward the side with more dissolved particles.

K stays constant during concentration or pressure changes but changes when temperature changes.

A catalyst speeds both directions equally, so equilibrium position does not change.

Equilibrium shifts can change measurable properties such as pH, color intensity, or temperature.

Pressure or volume changes shift gas equilibria toward fewer or more moles, unless gas moles are equal.