一、“对流”演示实验的改进 初三物理第二章关于对流的演示实验,课本介绍的方法虽然可行,但由于高锰酸钾极易溶于水,把它放入烧瓶后,晶粒下降过程中很快就染脏清水,并且在加热时会加快高锰酸钾的溶解,不易看出紫色溶液的“一股股细流”上升。对此,我们做了如下改进: First, the “convection” demonstration experiment to improve the third day of the physical physics The second chapter on the convection demonstration experiment, textbook description method is feasible, but because potassium permanganate is easily soluble in water, put it into the flask, the crystal drop Dirty water was quickly stained during the process, and the potassium permanganate was dissolved during heating, and it was not easy to see the “trickle stream” of the purple solution rise. In this regard, we have made the following improvements: