化合价是初中化学重要的知识点之一,它既是学习的重点,也是学习的难点。要理解和掌握这一概念,应注意以下几个方面。一、理解化合价实质化合价的定义是:一种元素一定数目的原子跟其他元素一定数目的原子化合的性质。这里要明确:1.化合价是属于元素的性质,而不是原子的性质。所以,要称化合价为元素的化合价。 Valence is one of the important knowledge points of junior high school chemistry. It is not only the focus of learning but also the difficulty of learning. To understand and master this concept, you should pay attention to the following aspects. I. Understanding valence The definition of substantial valence is the property of a certain number of atoms of one element combined with a certain number of atoms of other elements. Here we must make clear: 1. Valence is the nature of an element, not the nature of an atom. Therefore, we must call valence as the valence of the element.