初中化学课本 P.169[实验5--2] 熔化的硝酸钾导电实验很不直观,教参及化学刊物介绍用 U 形管代替瓷坩埚,但受热面积宽,加热时间长,U 形管一般加热易炸裂。我作了如下改进,效果很好。装置见第23页右下图。主要用品--试管1支,硬质玻璃管1支,铜条(或粗铜丝)2根, Junior middle school chemistry textbook P.169 [Experiment 5-2] The molten potassium nitrate conductivity experiment is not intuitive. The teaching and chemical publications describe U-tube instead of porcelain enamel. However, the heated area is wide, the heating time is long, U-shaped tube is generally Heating easily burst. I made the following improvements and it worked well. See the lower right picture on page 23 for the device. Main supplies--one test tube, one rigid glass tube, two copper rods (or thick copper wire),