关于“溶解度”和“析出物”的计算,是学生难于弄清的问题。对此类问题的一般解法,总有过程复杂、思维不简洁的毛病。笔者在教学活动中,尝试用“比例法”和“守恒法”去解题、不仅适于一般情况、特别是对于较复杂的题目,更有化难为易的效果。现介绍如下。 The calculation of “solubility” and “precipitate” is a problem that students find difficult to clarify. The general solution to such problems is always complicated and the thinking is not concise. In the teaching activities, the author tries to use the “proportional method” and the “conservation method” to solve the problem. It is not only suitable for general situations, especially for more complex topics, but also has more difficult effects. The introduction is as follows.