初中三年级学生初次接触化学这门学科时,一般对化学现象发生很大兴趣,但是对化学概念的理解能力很差,抽象思维能力更差。因此,要求学生用原子、分子的知识解释化学反应的实质、物理变化和化学变化、溶解平衡等内容时,答案叙述不是不清楚,就是不完整,表明他们对这些内容似懂非懂。所以这些内容是教学上的难点。后来我们改进了教学方法,运用自制挂图和彩色粉笔板书等来配合讲解,取得了 When junior high school students were exposed to chemistry for the first time, they were generally interested in chemical phenomena, but they had poor understanding of chemical concepts and poor abstract thinking ability. Therefore, when students are required to use atoms and molecules to explain the nature of chemical reactions, physical changes and chemical changes, dissolution balance, etc., the answer is either unclear or incomplete, indicating that they are ignorant of these contents. Therefore, these contents are difficult to teach. Later, we improved our teaching methods and used homemade wall charts and colored chalk boards to explain