针对近年考生失分严重的问题,总结了化学反应先后次序的类型及判断原则,既有利于学生巩固、掌握基础知识,又有利于学生解决实际问题. In view of the serious problem of losing score in recent years, this paper summarizes the types and judgment principles of the sequence of chemical reactions, which not only helps students to consolidate and acquire basic knowledge, but also helps students to solve practical problems.