Do Now Name the different factors that effect reaction rates and describe the different effects that ONE of them has on a reaction.

What is Equilibrium?

Objective 1 Explain that equilibrium is established when forward and reverse reaction rates are equal.

What is chemical equilibrium? Turns out that most reactions are reversible, they are going forward and backwards all the time Reversible Reaction: A + B  C ARROWS FOR REVERSIBLE REACTIONS Both products and reactants are present http://www.youtube.com/watch?v=LMIbJ-B92Ho&feature=related

Chemical Equilibrium Chemical Equilibrium: The point at which the rate of the forward and reverse reactions are equal.

How does equilibrium look? Equilibrium Position: The relative concentrations of reactants and products when they reach equilibrium

Objective 2 Describe how the rate of chemical equilibrium will shift when altering the various environmental and physical conditions.

Real-World Example The Human Body is AMAZING!!! Did you know that your body works to maintain dynamic equilibrium constantly. Cells-Nutrients flowing in/out Breathing-CO2 and O2 Bloodstream-HCO3- /CO32- Temperature Regulation

Le Chatelier’s Principle What factors effect the equilibrium of a reaction? Changing concentration Changing pressure Changing temperature These all produce a SHIFT in the equilibrium of a reaction A SHIFT means that either more reactants or products are produced

Changing Concentration Will always shift the reaction from the larger concentration to the smaller concentration.

Changing Pressure First, count the molecules (coefficients) If pressure increases If pressure decreases

Changing Temperature If temperature increases the exothermic reaction will be favored. If the reaction gets hotter it will try to cool down. If temperature decreases the endothermic reaction will be favored. If the reaction gets cooler it will try to heat up.

Le Chatlier’s Principle If a dynamic equilibrium is disturbed by changing the conditions, the position of equilibrium moves to counteract the change. WRITE THIS DOWN

Let’s look at Temperature Again Is this equation Endothermic or exothermic? What is H? Where would heat appear in the equation?

Changing temperature http://www.youtube.com/watch?v=BGfYf8OQzuk http://www.youtube.com/watch?v=tlGrBcgANSY&feature=related

Shifting an Equilibrium There are 3 ways to shift an equilibrium Concentration of products or reactants Changing temperature Changing pressure

Exit Slip: Equilibrium Title your paper “Exit Slip: Equilibrium” Write your name, date, and period. Number your paper 1-4 

Crash Course Equilibrium Video

Classwork You are to work on the worksheet you received at the beginning of the class period.

Exit Slip: Equilibrium 2H2O2  2H2O + O2 + Heat If I add heat, to which side will the eq. shift? If I remove heat, to which side will the eq. shift? If I add more H2O2, to which side will the eq. shift? If I add more O2, to which side will the eq. shift?