化合价教学的几点想法

Analyse on Valency Teaching

初中化学用语主要有三种：元素符号、化学式、化学方程式。有两个阶梯：元素符号一化学式一化学方程式，化合价是学生实现化学用语二步阶梯的重要工具，很重要但较难掌握，如何突破这个难点，通过多年的化学教学，笔者在本文中提出了应注意的几个问题。

The frequently-used chemistry expressions 3 kinds： the symbol of element, the chemical formula and the chemical equation. There are tow steps in learning chemical equation： symbol of element→chemical formula→ chemical equation. In those steps, valency is an important but diffcult part for the students to achieve the second step. With rich valency teaching experience, the author of this paper raises some advices for helping the students to solve this problom, and also some notice in teaching valency.