The new textbook of high school chemistry has been used for many years. The content and arrangement of the textbook are structured and systematic, involving the essence of knowledge and providing rich materials. The " elective 2 material structure and properties " is a difficult curriculum system for teachers to prepare lessons and teach. The main content of the textbook is to study the " relationship between structure and properties " on a certain particle scale, and the teaching goal is to memorize, understand and apply the " structure ". At present, there are few studies on the textbook analysis of this textbook. Based on the author "s teaching practice and textbook analysis, this paper expounds the difficulties ( concepts and experiments ), the key points ( students " thinking development points ), the difficult problems ( frontiers of science and technology ) and the doubts ( teachers " myths ) of the third chapter " crystal structure and properties ".