EQUILIBRIUM SUMMARY

1. Equilibrium has been reached when concentrations no longer change over time.
2. The equilibrium constant of a reaction in the reverse direction is the inverse of the equilibrium constant of the reaction in the forward direction
3. The equilibrium constant of a reaction that has been multiplied by a number is the equilibrium constant of the reaction raised to a power equal to that number
4. The equilibrium constant for a net reaction made up of two or more steps is the product of the equilibrium constants for the individual stepsIf K >> 1 (big) then equilibrium lies to the right (products)
5. If K <<>
6. Leave solids and pure liquids out of equilibrium expressions, the concentration of these substances does not change with time.
7. Calculating Equilibrium Constants; is easy when we know all the equilibrium concentrations (or pressures), a balanced equation, and can write a rate expression.
8. When we know initial concentrations and an equilibrium concentration, use the stoichiometric coefficients to predict the change in concentrations.U se the Initial, Change, Equilibrium (ICE) procedure to find all the equilibrium concentrations and sub these values into the equilibrium expression
9. Calculating Equilibrium Concentrations; when we know K and all the initial concentrations only, use the ICE procedure and solve for x the change in concentration, possibly by solving a quadratic function.

Click on any of the links below for online quizzes on different aspects of equilibrium!

http://library.thinkquest.org/C006669/data/Chem/quizzes/equilibrium.html

http://lrc-srvr.mps.ohio-state.edu/under/chemed/qbank/quiz/bank11.htm

http://www.sciencegeek.net/Activities/lechatelier.html

http://www.sciencegeek.net/Activities/equilcalcconc.html

http://www.sciencegeek.net/Activities/calcK.html

This science teacher has posted videos on Youtube, reviewing everything that we have learned this year, including equilibrium, kinetics, bonding, stoichiometry, atomic theory, the mole, acids and bases, redox, and energetics. His reviews are short and easy to follow! The link below will take you to the 100 videos he has posted so far: you will have to look through them for the equilibrium videos (on page 4), or watch all of them.

http://www.youtube.com/view_play_list?p=959A532E49F9F95C&page=1