Potential Energy Diagrams

Burning Magnesium

Exothermic Reaction ___________________________

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_________________

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.

Endothermic Reaction _____________________

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.

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 _________.

SUMMARY