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dA]/[A]2=-k2d,两边积分得: a. The second-order rate equation: 1/[AJt=1/[AJo+k2t b.在二级反应中,以反应物浓度的倒数对时间t作图,呈一条直线,其斜率为k2 c.二级反应的半衰期:1 +k、t [Al/2[A0 k2[A10 可见,二级反应半衰期与起始浓度的一次方呈反比,即反应物起始浓度越大,n1/2越 小。下列反应均是二级反应: NO(g)+Co(g) NO(g)+CO2(g) rate=k2[NOI[Co] CH3 COOC2Hs(aq)+OH (aq) CH3 COO(aq)+ C2HsOH(aq) OC2HSJ[OH I 2NO2(g) 2NO(g)+O(g) rate=k2(NO2]- 四、反应速率与温度的关系( The relationship of rates and Temperature) 1.根据许多实验事实,总结出一条近似的经验规则,温度每升高10℃,反应速率大约 增大2~4倍,即k1+10/k1=2~4。这是van' t Hoff归纳出来的一个近似的经验规 律。有时又称为Van' t Hoff 's rule. 2.1889年瑞典科学家S. Arrhenius总结了大量的实验数据,得出了如下结论: 化学反应的速率常数(k)与温度之间呈指数关系 =-1.2×10K -1000 T(K) -100 △(l/7 Figure 3.4 10-3 A plot showing the exponential dependence of the rate constant /T(K) on absolute temperature. The Figure 3.5 exact temperature dependence of k is different for each reaction Plot of In(k) 1/T for the reaction 2N 4NO2(g)+ This plot represents the behavior O2(g). The ve the activation of a rate constant that doubles for every increase in temperature obtoigy for this reaction can be ed from the slope of the of 10 K line, which equals -E/R 3.公式:k=A·e The arrhenius equation ItH Eathe activation energy A-the frequency factor, it is related to the frequency of collisions and the probability that the collisions are favorably oriented for reaction54 d[A] / [A]2 = −k2dt ,两边积分得: a.The second - order rate equation:1 / [A]t = 1 / [A]0 + k2t b.在二级反应中,以反应物浓度的倒数对时间 t 作图,呈一条直线,其斜率为 k2 c.二级反应的半衰期: 2 1/2 0 0 1 1 = + [A] / 2 [A] k t ∴ 1/ 2 2 0 1 [A] t k = 可见,二级反应半衰期与起始浓度的一次方呈反比,即反应物起始浓度越大,t1 / 2 越 小。下列反应均是二级反应: NO2(g) + CO(g) NO(g) + CO2(g) rate = k2[NO2][CO] CH3COOC2H5(aq) + OH- (aq) CH3COO- (aq) + C2H5OH(aq) rate = k2[CH3COOC2H5][ OH- ] 2NO2(g) 2NO(g) + O2(g) rate = k2[NO2] 2 四、反应速率与温度的关系(The Relationship of Rates and Temperature) 1.根据许多实验事实,总结出一条近似的经验规则,温度每升高 10℃,反应速率大约 增大 2~4 倍,即 k t +10 / k t = 2~4。这是 Van’t Hoff 归纳出来的一个近似的经验规 律。有时又称为 Van’t Hoff’s rule. 2.1889 年瑞典科学家 S. Arrhenius 总结了大量的实验数据,得出了如下结论: 化学反应的速率常数(k)与温度之间呈指数关系。 3.公式: a E RT / k A e− =  ──The Arrhenius equation 式中 Ea─ the activation energy A─ the frequency factor, it is related to the frequency of collisions and the probability that the collisions are favorably oriented for reaction
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