比较溶液中离子浓度的大小关系及其有关的计算是历年高考中的一个必考知识,是高中化学中的一个重点、难点,解决这类难题的其中一个关键往往在于是否能正确书写溶液中的“三个守恒”关系。“三个守恒”即原子守恒(物料守恒)、电荷守恒和质子守恒。笔者通过几个典例对以上“三个守恒”的书写加以说明。—、单一溶液例1.写出Na_2S溶液中三个守恒关系。 Comparison of the size of the ion concentration in solution and its related calculations is a compulsory knowledge in college entrance examination over the years, is a high school chemistry, the difficulty, one of the key to solve these problems often lies in whether the correct solution can be written in “Three Conservation ” relationship. “Three conservation ” that is atomic conservation (material conservation), conservation of charge and conservation of protons. The author through several examples of the above “three conservation ” writing to illustrate. -, Single Solution Example 1. Write out the three conservation relationships in the Na_2S solution.