论文部分内容阅读
本章演示实验有十几个,着重树立学生对“物质由分子构成”的概念。其中如溴的扩散、高锰酸钾的扩散都是给予学生“物质由分子构成”初步认识的重要演示。初中化学以原子分子论为中心,所以本章的演示实验要求教师们一定作得清楚正确,以便给以后各章的学习打下基础。这些演示都是初次给学生们看,所以应该在进行演示之先要把仪器的名称,使用的试剂以及演示的目的一一简单地告诉学生;并应对使用的仪器是否明亮光洁,试剂的质量是否合适课前加以检查,即使授课多年的教师也应仔细地准备。此外,对於演示实验的布置必须能达到在演示进行中,使学生们看得清楚;同时把观察的现象随时加以分析,最后得出正确的结论。
This chapter demonstrates more than a dozen experiments, focusing on setting the student’s conception of “matter composed of molecules.” Among them, such as the proliferation of bromine, potassium permanganate diffusion are given students an important demonstration of the initial understanding of “matter from the molecular structure.” Junior high school chemistry is centered on atomic molecular theory, so the demonstrations in this chapter require that teachers must be clear and correct in order to lay the groundwork for future chapters. All of these presentations are for the first time presented to the students. Therefore, students should be informed of the name of the instrument, the reagent used and the purpose of the demonstration briefly before proceeding with the demonstration. The instrument should be bright and clean, and the quality of the reagent Check the appropriate class, even if the teacher taught for many years should be carefully prepared. In addition, the layout of the demonstration experiment must be able to achieve the demonstration in progress, so that students can see clearly; at the same time observe the phenomenon at any time be analyzed, and finally come to the correct conclusion.