一、化学实验教学,要引导学生观察,积极进行思维,正确形成概念现行初中化学教材安排的课堂演示实验、学生实验,为初进化学之门的人提供了丰富的感性材料。因此,正确观察实验发生的现象,接受实验传递的信息,便成了实验教学的重要任务。在实验观察中,除了观察物质的颜色、状态、硬度、气味、比重、溶解性等现象外,还要观察反应过程中出现的现象,如熔化、升华、气泡、沉淀、颜色、放热、吸热、燃烧、闪光、发声、爆炸等等。对稍纵即逝的,或隐蔽的现象更要精细地观察。比如“绪言”中提到的镁带燃烧实验,使学生观察到镁带 First, the chemical experiment teaching, to guide students to observe, actively thinking, correctly formed the concept of the current junior high school chemistry textbook classroom demonstration experiments, student experiments, for the entrance of the door of chemistry provides a wealth of perceptual material. Therefore, it is an important task for experimental teaching to correctly observe the phenomena that occur in the experiment and receive the information conveyed by the experiment. In the experimental observation, in addition to observe the color, state, hardness, odor, specific gravity, solubility and other phenomena, but also observe the phenomenon of the reaction process, such as melting, sublimation, bubbles, precipitation, color, heat, Hot, burning, flashing, vocal, explosion and more. To the fleeting, or more subtle phenomenon to be observed. For example, the “Introduction” mentioned in the magnesium combustion test, so that students observe the magnesium zone