溶液中离子是否大量共存是常考的选择题型,由于条件变化多端,共存情况复杂,往往使学生判断失误。其实,只要掌握好离子共存问题包括的内容,问题就会迎刃而解。当然也要注意题干条件,如“一定能”“可能”“一定不能”“无色”“因发生氧化还原反应”等。经过不断思考,我归纳总结为一句话:一色、二性、三可能、四反应、五特殊。 Whether a large number of ions coexist in the solution is often the choice of test questions, due to the changing conditions, the coexistence of complex situations, often make students judge mistakes. In fact, as long as you master the content of ion coexistence issues, the problem will be solved. Of course, we must pay attention to the dry conditions, such as “must ” “may ” “must ” “colorless ” “due to the occurrence of redox reaction ” and so on. After continuous thinking, I summed up as one sentence: one color, two sexes, three possible, four reactions, five special.