第二章化学反应速率 Chapter 2 Rates of chemical reacti 化学反应速率与化学达到平衡的倾向的区别 We saw that a reaction with a very large equilibrium constant has a strong tendency toward the products so that very little of the reactants remain when equilibrium is reached. Such a reaction is said to be spontaneous. However, as we have already pointed out, spontaneous doesn't mean fast In order to be able to control the rates of reactions, we need to understand the Many reactions of industrial importance employ catalysts, and most reactions in living organisms are catalyzed. We will discuss how a catalyst can increase the rate of a reaction without being used up First we need to consider just how we express and measure the rate of 21速率及表示方法( Reaction rate) The rate of a chemical reaction is defined as the change in the concentration of a reactant (or product) in a given time interval. Consider the reaction between A and B aA+bb=gg+dD d d c 反应速率v的单位mom3s(摩尔每立方米秒),B表示B的浓度随时 间的变化率。这样定义的反应速率v与物质的选择无关。 22浓度、温度、催化剂对反应速率的影响 不同的化学反应,反应速率不同,同一反应在不同的条件下进行时反应速率 也不同。影响反应速率的因素除与反应物的本质、浓度、温度外,还有催化第二章 化学反应速率 Chapter 2 Rates of chemical reactions 化学反应速率与化学达到平衡的倾向的区别。 We saw that a reaction with a very large equilibrium constant has a strong tendency toward the products so that very little of the reactants remain when equilibrium is reached. Such a reaction is said to be spontaneous. However, as we have already pointed out, spontaneous doesn’t mean fast. In order to be able to control the rates of reactions, we need to understand the factors that influence the rate. Many reactions of industrial importance employ catalysts, and most reactions in living organisms are catalyzed. We will discuss how a catalyst can increase the rate of a reaction without being used up. First we need to consider just how we express and measure the rate of a reaction. 2.1 速率及表示方法(Reaction rate) The rate of a chemical reaction is defined as the change in the concentration of a reactant (or product) in a given time interval. Consider the reaction between A and B. aA+bB=gG+dD dζ= B B dn  dt dc v B B  = 反应速率 v 的单位 mol.m-3 .s-1 (摩尔每立方米秒)， dt dcB 表示 B 的浓度随时 间的变化率。这样定义的反应速率 v 与物质的选择无关。 2.2 浓度、温度、催化剂对反应速率的影响 不同的化学反应，反应速率不同，同一反应在不同的条件下进行时反应速率 也不同。影响反应速率的因素除与反应物的本质、浓度、温度外，还有催化