“化合价”在初中化学教材中,要算比较难以理解的一节。假如不用通俗的实例,引伸导入,乍以抽象的理论,空泛地讲解,学生最易模糊。尤其这一“化合价”对以后学习门捷列夫“周期表”有互相关联的。所以教到这一节教师必须要耐心地备课,结合学生现有水平,用浅显通俗的方式使学生明确“化合价”的初步定义,及怎样利用“化合价”写出正确的分子式。现在我把这一节教学过程,分别提出,以供参考。一、化合价的初步认识两种元素化合的时候,其中一种元素的一个原 “Valence” in junior high school chemistry textbooks, to be considered a more difficult to understand section. If you do not use popular examples, the introduction of extension, abstraction to explain the theory, explain in vague, students most vague. In particular, the “valence” is related to the study of Mendeleev “Periodic Table” in the future. Therefore, teaching this section teachers must patiently prepare lessons, combined with the current level of students, with a simple and easy way to enable students to clear the “valence” of the initial definition, and how to use “valence” to write the correct formula. Now I put this section of the teaching process, respectively, for reference. First, the valence of the initial understanding of two elements when combined, one of the elements of a