Unit 4: Chemical Equilibrium


  1. Understand the nature and characteristics of chemical equilibria
  1. Chemical reactions are reversible and equilibria are dynamic
  1. Understand the significance of the equilibrium constant, K, and reaction quotient, Q.
  1. Write the reaction quotient, Q, for a chemical reaction. When the system is at equilibrium, the reaction quotient is called the equilibrium constant, which is symbolized by K
  2. Recognize that the concentrations of solids, pure liquids, and solvents (e.g., water) are not included in the equilibrium constant expression.
  3. Recognize that a large value of K (K>1) means the reaction is product-favored, and that a small value of K (K<1) indicates a reactant-favored reaction.
  4. Appreciate the fact that equilibrium concentrations may be expressed in terms of concentration (Kc), or, for gases, in terms of partial pressure (Kp)
  1. Understand how to use K in quantitative studies of chemical equilibria
  1. Use the reaction quotient to decide whether a reaction is at equilibrium (Q=K), or if there will be a net conversion of reactants to products (Q<K) or products to reactants (Q>K) to attain equilibrium.
  2. Calculate an equilibrium constant given the reactant and product concentrations at equilibrium.
  3. Use equilibrium constants to calculate the concentration (or pressure) of a reactant or a product at equilibrium.
  4. Know how to predict the effect of a disturbance to an equilibrium system (LeChâtelier’s Principle)