1. Potential Energy Diagrams

2. Burning Magnesium

3. Exothermic Reaction ___________________________

4. Key
Potential energy of the reactants _________________________________
Potential energy of the activated complex__________________________
Potential energy of the products _________________________________
Activation energy for the forward reaction__________________________
Activation energy for the reverse reaction__________________________
 H (Exothermic__________________; Endothermic______________)
Potential energy of the activated complex with catalyst _______________
Activation energy of the forward reaction with catalyst________________
Activation energy of the reverse reaction with catalyst_________________

5. Endothermic Reaction
QUESTION: How would the potential energy diagram change for an endothermic reaction with and without a catalyst?
CLAIM: With your lab partner draw and label a potential energy diagram for the decomposition of magnesium oxide. Include your labeled diagram on the next slide.

6. Endothermic Reaction _____________________

7. EVIDENCE (fill in the following information from your graphs)
Exothermic
Endothermic
a. In an exothermic reaction the heat of the reactants is ______ than the heat of the products.
b. A catalyst _______ the activation energy.
a. In an endothermic reaction the heat of the reactants is _______ than the heat of the products.
b. A catalyst ______ the activation
energy.

8. REASONING: (Explain your evidence)
Exothermic
Endothermic
An exothermic reaction _______ heat because the heat of the reactants is _____ than the heat of the products.
A catalyst ______ the rate of a reaction by________________ but the heat of reaction ________.
An endothermic reaction _______ heat because the heat of the reactants is _______ than the heat of the products.
A catalyst ______ the rate of the a reaction by _____________ but the heat of the reaction _________.

9. SUMMARY