化学动力学English.ppt

Chapter 3 Chemical kinetics §3.1 Chemical reaction rates 3.1.1 Average rates and instantaneous rates of chemical reactions 3.1.2 Chemical reaction rates under  constant volume conditions §3.2 Effect of concentration of  reactants on reaction rate —the rate expression 3.2.1 The rate expression 3.2.2 Determination of the rate  expression — the initial rate method 3.2.3 Relation between reactant  concentration and time §3.3 Effect of temperature on reaction  rate —Arrhenius equation 3.3.1 Arrhenius equation 3.3.2 Application of the Arrhenius equation 3.3.3 Further analysis of Arrhenius equation §3.4 Theory of reaction rate and reaction mechanisms 3.4.1 Collision theory of reaction rates 3.4.2 Activated complex theory (Transition state theory) 3.4.3 Activation energy and reaction rate 3.4.4 Reaction mechanism and elementary reactions §3.5 Catalyst and catalysis 3.5.1 Catalysts and basic features of  catalysis 3.5.2 Homogeneous catalysis and  heterogeneous catalysis 3.5.3 Enzyme Catalysis Activated complex theory is based on the study of energy change in chemical reaction process. In this theory, the collision of the reactant molecules results in the formation of an activated complex. 活化络合物所处的状态叫过渡态。 Example： The activated complex having high potential energy Eac is and unstable. It decomposes to products NO2 and O2 quickly。 N O O O O The energy changes in chemical reactions Ea(逆) (正) (正) Ea(逆) Eac Eac E(Ⅰ)－potential energies of reactants (initial state) E(Ⅱ)－potential energies of products (final state) Activation energy of a forward reaction Ea (forward) =Eac - E(Ⅰ) Activation energy of a reverse reaction Ea ( reverse) =Eac - E(Ⅱ) ΔrHm= E(Ⅱ) - E(Ⅰ)= [Eac - Ea(reverse)] -[Eac -Ea(forward)] ΔrHm= Ea(forward )