武汉大学：《物理化学 Physical Chemistry》课程教学资源（PPT课件讲稿）Phenomenological Chemical Kinetics（empirical/classical）Physical Chemistry II

Phenomenological Chemical Kinetics (empirical/classical) Physical Chemistry II 1. Reaction Rate rate equation 2. Theoretical consideration -sct TsT 3. Microscopic Mechanism

Physical Chemistry II Phenomenological Chemical Kinetics (empirical/classical) 1. Reaction Rate & Rate Equation 2. Theoretical Consideration – SCT & TST 3. Microscopic Mechanism

与讲过的热力学大不相同 热力学 力 过程的可能性 过程的快慢 过程的自发性 过程的步骤 过程的可逆性 过程的机制 方向和程度 速率 概念理解 推导

与讲过的热力学大不相同: 热力学 动力学 过程的可能性 过程的自发性 过程的可逆性 过程的快慢 过程的步骤 过程的机制 方向和程度 速率 概念理解 推导

Three characteristics of a chemical reaction 1)Stoichiometric characteristics: balance of the equation 2)Thermodynamic characteristics: Spontaneity and equilibrium 3)Kinetic characteristics: Rate and mechanism

Three characteristics of a chemical reaction 1) Stoichiometric characteristics: balance of the equation 2) Thermodynamic characteristics: Spontaneity and equilibrium 3) Kinetic characteristics: Rate and mechanism

EI ectronic work Air Work Food 开放系统 Expansion eat Heat How fast? Why different?

开 放 系 统 Food Air Heat Work Electronic work Work Expansion Heat How fast? Why different? Kinetics

The factor concerned by thermodynamics is the inherent tendency or the possibility of the reaction but not eat and rate C(diamond)->C(graphite) is spontaneous, but it is so so that it is not detectable

The factor concerned by thermodynamics is the inherent tendency or the possibility of the reaction but not reality and rate. C (diamond) → C (graphite) is spontaneous, but it is so slow that it is not detectable

Chemical kinetics the area of chemistry that concerns reaction rate Main concerns of chemical kinetics 1) Reaction rate: the factors that determines the rate of reaction and rate law

Chemical kinetics: the area of chemistry that concerns reaction rate. Main concerns of chemical kinetics: 1) Reaction rate: the factors that determines the rate of reaction and rate law

2) Reaction mechanism: the series of steps by which a reaction takes place. 3) structure-dependence of reactivity The correlation between molecular structure and reaction ability

2) Reaction mechanism: the series of steps by which a reaction takes place. 3) structure-dependence of reactivity. The correlation between molecular structure and reaction ability

Reaction mechanism and elementary reaction Reaction mechanism /reaction pathway the detailed way by which the reactants are converted into products, or the series of steps by which a reaction takes place

the detailed way by which the reactants are converted into products, or the series of steps by which a reaction takes place. Reaction mechanism and elementary reaction Reaction mechanism / reaction pathway detailed way series of steps

H2+12=2HI Kinetic experiments suggest that this reaction occurring as follows 1)2=2I 并不是相当然的 也不是表面的东西 2)2I+H2=2HI

H2 + I2 = 2 HI Kinetic experiments suggest that this reaction occurring as follows: 1) I2 = 2I 2) 2I + H2 = 2HI 并不是相当然的, 也不是表面的东西

H+ Br=2 HBr 1) Br2=2 Br 2) Br+ H2=HBr+H 3)H+ Br2=HBr+ Br 4)H+ HBr= h2+ Br 5)2 Br= Br

H2 + Br2 = 2 HBr 1) Br2 = 2 Br 2) Br + H2 = HBr + H 3) H + Br2 = HBr + Br 4) H + HBr = H2 + Br 5) 2 Br = Br2 More complicate!