现行初中化学课本关于二氧化锰催化作用的实验有三个[1-6;1-7;1-8],如按课本上的顺序实验,很难在一课时内完成,为了节省时间,说明问题,克服往试管里撒入二氧化锰操作上带来的困难,当堂完成教学内容,可将实验改进如下: 方法一 1.各取一药匙氯酸钾,分装(用纸槽)于两支小型试管中,往其中一支试管里装入少量的二氧化锰,[说明1-8改为氯酸钾与二氧化锰混和加热]。 There are three [1-6; 1-7; 1-8] experiments on manganese dioxide catalysis in the current junior middle school chemistry textbook. If the experiment is based on the sequence of textbooks, it is difficult to complete within one lesson time. To save time, explain the problem. In order to overcome the difficulties brought about by the operation of diffusing manganese dioxide into test tubes, the following experiment can be modified as follows: Method 1 1. Take one medicine spoon of potassium chlorate and dispense (with a paper tank) in two. In a small test tube, put a small amount of manganese dioxide into one of the tubes, [Note 1-8 instead of potassium chlorate mixed with manganese dioxide heating].