本题目来源于试卷: How Much How Fast & How Far E.2 Rate of Chemical Change，类别为 IB化学
[单选题]
Two experiments were condp* qsee, ij3 os(7le(vucted, and the rates of reactions wsy a9wu.(8m ifere measured. In the first experiment(f9 a msiwu8y., 50$cm^3$of 0.010$mol$ $dm^{-3}$of sulfuric acid was added to 0.200$g$of zinc metal at $25^{\circ}C$. In the second experiment, 50 $cm^3$of 0.010 $mol$ $dm^{-3}$of sulfuric acid was added to 0.200$g$$25^{\circ}C$, followed immediately by 100$cm^3$of distilled water. What happened to reaction rate in the second experiment, and why?
A. Rate of reaction is increased because water lowers the activation energy
B. Rate of reaction decreased since the frequency of effective collisions between reactant molecules lowered
C. Rate of reaction increased because the proportion of reactant molecules possessing the activation energy lowered
D. Rate of reaction increased because there are more particles in the solution, and the frequency of effective collisions increased
参考答案: B
本题详细解析:
B Adding water will reduce the concentration (dilution), and, therefore the frequency of effective collisions will decrease.
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