Changing concentrations of
substances at equilibrium
Changing of the amounts of reacting species can be considered in two
cases:
◦ If the reactants are added into the system, reaction will proceed to
the right and produce more products. This is the same result as if we
remove the products from the system.
◦ If the products are added to the system, the reaction will proceed to
the left and produce more reactants. Again, this is the same result as
if we reduce the concentrations of reactants.
◦ NOTE: adding or removing pure solid or pure liquid in a heterogeneous
equilibrium mixture will have no effect in the equilibrium condition.