Topic 11, Equilibrium
Topic 11, Equilibrium
(Key Concepts)


Equilibrium:
*During equilibrium, the rates of the forward and reverse reactions are equal.
*During equilibrium, the concentrations of the reactants and the products are constant.
*Phase equilibrium:  H2O(l) <=> H2O(g)
*Solution equilibrium: 
NaCl(s) <=> Na+(aq) + Cl-(aq)
*Chemical equilibrium:
2H2(g) + O2(g) <=> 2H2O(g) + energy


*A saturated solution is at equilibrium.


Le Chatelier's:
*Changes in concentration, temperature, and pressure (if gas present) stress an equilibrium and shift (left or right) the equilibrium in a way to relieve the stress. 
*An equilibrium shifts away from an increase in concentration or temperature.
*An equilibrium shifts toward a decrease in concentration or temperature. 
*If there are different amounts (# of moles, volumes) of gases on the left versus the right, an increase in pressure will favor the smaller number/volume of gases.  A decrease in pressure will favor the larger number/volume of gases.