Unit 2: Equilibrium Lesson 1: The Concept of Equilibrium

The Concept of Equilibrium Last unit, you learned that reactions can go both backward and forward, that is, they are reversible. A reversible reaction is said to be at equilibrium when the rate of the forward reaction is equal to the rate of the reverse reaction. We are going to simulate this using beakers of water... Show basic concept using water demo (use volunteers!), then elaborate on each concept on the next slide... – 5 min

At equilibrium... Rate of consumption of reactants = rate of production of reactants. [Reactants] usually differs from [Products]. [Reactants] and [Products] are constant in time. The forward and reverse reaction rates do not change as time passes. A system which is not at equilibrium will tend to move toward equilibrium. 10 min

Brain Break!

Demo: Reaction in a Bottle Describe the contents of the bottle. What happens when the bottle is shaken? Why doesn’t it stay blue? The contents of the bottle are in equilibrium: X + O2 Y X is colourless and Y is blue. Shaking the bottle increases the amount of available oxygen and shifts the equilibrium system. Blue bottle demo - http://www.rsc.org/learn-chemistry/resource/res00000729/the-blue-bottle-experiment?cmpid=CMP00005928 – prepare in advance but as close to class time as possible. – 15 min

Your Turn! Working in a group of three, come up with your own analogy for equilibrium. You have ten minutes to brainstorm, then you will briefly present your analogy to the class. Your presentation may be in the form of a skit, a chalkboard drawing, or a demonstration... Don’t just stand and talk! 15 min

No homework!