在化学教学中,每年都要开设“萃取”这个实验,目的是既要验证课堂理论--分配定律,又要培养学生基本操作,所以是必不可少的。此实验的内容是利用碘在互不相溶的水与四氯化碳两种溶剂中的溶解度相差约87倍这个关系来做的,比较容易理解。但是,每个学生实验后就会留下几十毫升的含碘四氯化碳溶 In chemistry teaching, the experiment of “extraction” should be set up each year. The purpose of this experiment is to verify the classroom theory - the law of distribution and the basic operation of students, so it is essential. The content of this experiment is made using the relationship between the solubility of iodine in two mutually incompatible water and carbon tetrachloride difference about 87 times, which is easy to understand. However, each student will leave tens of milliliters of iodine-containing carbon tetrachloride after the experiment