Chemical Equilibrium
– The point at which the forward and reverse processes of a chem. rxn are occuring at the same rate
Conditions of Equilibrium
– both the forward & reverse reactions are occuring
– both the forward & reverse rxns are happening at the same rate
– once equilibrium is achieved the concentration of each reactant & product remain the same
The equilibrium Constant (Keq)
– the ratio of the rate constants is a constant at that temp, this expression is called the law of mass action
Equilibrium Constants in terms of Pressure
– When reactants & products are both gases the equilibrium expression is then written for partial pressures instead of molar concentrations
Relationship between Kc & Kp
– Kp = Kc (RT)^Deltan
– change in N= (moles of gaseous products)-(moles of gaseous reactants)
– R= .0821
Homogeneous Equilibrium
– Equilibria in which all the reactants and products are present in the same phase
Heterogenous Equilbrium
– Equilibria where one ore more reactants or products are present in a different phase are called heterogeneous equilibria
Hterogenous Equilbrium (cont.)
– If a pure solid (s) or pure liquid (l) is involved in a heterogenous equilibrium it’s concentration is not included in the equilibrium constant expression
Interpreting & Working w/ Equilibrium Constants
– if the K equilibrium constant is >> 1 than the equilibrium lies to the right, the products dominate
Interpreting & working w/ Equilibrium Constants
– if the K equilibrium is << 1 the equilibrium lies to the left and the reactants dominate
The Direction of Chemical Equation & K
– The equilibrium constant for a reaction in one direction is the reciprocal of the equilibrium constant of the reaction in the opposite direction