小学自然教学实验指导中,介绍验证气体热胀冷缩的方法有三种,其中一种方法是用玻璃瓶塞上一个带有“L”型玻璃弯管的实验。我在应用此法进行演示实验时,发现其设计有所欠缺,不仅操作难度大,而且观察现象不够明显,现做如下改进,即将“L”型弯管改换成“N”型弯 In the primary school nature teaching experiment guide, there are three ways to verify the thermal expansion and contraction of gas. One of the methods is to plug a glass bottle with an experiment of “L” type glass elbow. When I applied this method to conduct demonstration experiments, I found that there was a lack of design. Not only was it difficult to operate, but the observation was not obvious enough. I made the following improvements to change the “L” elbow to “N”