10.5 - Equilibrium Constants

• what is the equilibrium constant?

  quantitative law for predicting the amounts of reactants and products present when a reaction reaches dynamic equilibrium

  gives you an idea how far to the left or right equilibrium is
• formula for the equilibrium constant

  ((C^c)*(D^d))/((A^a)*(B^b))

  capital letters=concentration of products and reactants in mol dm^3

  lowercase letters are coefficients on the balanced equation

  C and D are products

  A and B are reactants
• homogenous equilibrium

  equilibrium system where all the substances are in the same phase (physical state)
• working out equilibrium constant for homogenous equilibria

  use concentrations of products and reactants at equilibrium

  don't include catalysts because they don't affect the position of equilibrium
• heterogenous equilibrium

  equilibrium system where substances are in more than one phase (physical state)
• working out equilibrium constant for heterogenous equilibria

  don't include solids or pure liquids because their concentrations stay constant throughout the reaction

  don't include catalysts because they don't affect the position of equilibrium