实验1:用镊子夹住一块石头在酒精灯火焰上烧一会儿,然后把这块石头放入冷水中,接着再烧、再浸入冷水中。反复几次,观察石块有什么变化?此实验进行分组操作,每组烧一块石头,有的因石头种类不同,而不能产生明显的效果,且反复几次花费的教学时间较长;教师进行演示可见度低,学生感知也不深刻,教学效果不理想。为此,我设计了如下分组实验器材:三角架、铁丝网、酒精灯、镊子及每人自备一个水杯。实验方法是让学生各自从 Experiment 1: Clamp a piece of stone with tweezers and burn for a while on the flame of an alcohol lamp. Then put the piece of stone in cold water, then burn it again, then dip it in cold water. Repeated several times to observe what changes stones? The experiment grouping operations, each group burning a stone, and some because of the different types of stones, and can not produce significant results, and repeatedly spent several hours of teaching longer; teachers Demonstration of low visibility, the students do not perceive profound, teaching is not satisfactory. To this end, I have designed the following group of experimental equipment: tripod, barbed wire, alcohol lamp, tweezers and each with their own glass. The experimental method is to let students from each