在实验教学中应用对比实验 ,有利于帮助学生形成化学概念 ,理解和巩固化学知识 ,掌握化学变化规律 ,进而提高学生分析问题和解决问题的能力。1　帮助学生形成和理解概念　　如 ,讲“催化剂”这一概念时 ,我就充分利用课本中三个演示实验作为对比 ,指导学生观察不同的现象 ,进行 The use of comparative experiments in experimental teaching is conducive to helping students form a chemical concept, understand and consolidate chemical knowledge, master the laws of chemical change, and then improve students’ ability to analyze problems and solve problems. 1 Help students to form and understand concepts When talking about the concept of “catalyst”, I will use three demonstration experiments in the textbook as a contrast to guide students to observe different phenomena and conduct