化学反应速度是中学化学重要基础理论知识。在高中教材中,通过碗代硫酸钠溶液跟稀硫酸反应的实验,根据析出一定量的硫使溶液变浑浊所需的时间,来说明化学反应速度的规律。这实验的优点是简单易做、通用性强。但由于观察者视力好坏不同,视觉暂留现象的存在及选择浑浊程度的标准不 The speed of chemical reactions is an important basic theoretical knowledge of middle school chemistry. In high school textbooks, the reaction of dilute sodium sulfate solution with dilute sulfuric acid is used to illustrate the law of chemical reaction speed based on the time required for precipitation of a certain amount of sulfur to make the solution cloudy. The advantages of this experiment are simple and easy to use and versatile. However, due to the difference in vision between the observers, the existence of vision persistence and the criteria for selecting turbidity are not