１增大演示实验的可见度 分子间存在着空隙是分子运动的初步知识的重要组成部分．为了能给学生一个直观的认识，课本上（华东版）采用的演示实验是：先在一根一端封闭的较长的玻璃管内注入一半水，再缓慢地倒入酒精．用塞子塞住开口端，上下颠倒几次再竖起来，让学生观察玻璃管 1 Increase the visibility of demonstration experiments The existence of voids between molecules is an important part of the preliminary knowledge of molecular motion. In order to give the students an intuitive understanding, the demonstration experiment used in the textbook (East China Version) was to inject half of the water in a long glass tube closed at one end, and slowly pour alcohol. Plug the open end with a stopper, turn it upside down a few times, and let students observe the glass tube.