From the perspective of ontology, this paper discussed the boundary and the research object of the discipline of chemistry didactics, divided the development of the discipline of chemistry didactics into two periods which include five stages, and summed up the characteristics of those five stages. From the perspective of methodology, this paper pointed out the future development of the discipline of chemistry didactics.

This paper aims to discuss the key changes of 2017 senior high school chemistry curriculum standards, especially about the nature and value of chemistry discipline, the meaning and structure of chemistry disciplinary core competencies, the chemistry curriculum content system, and the design of competency-based chemistry classroom teaching.

In order to measure the students' comprehension level of acid-base reaction, and to diagnose the students' alternative framework, this paper developed test tool for understanding the concept of acid-base reaction based on the RASCH model, and used this tool to test 752 students. The analysis showed that the test results had certain reliability and validity. The test results also showed that senior high school students' conceptual understanding of acid-base reaction increased with the grade, but there were many alternative frameworks in different comprehension levels.

Using metaphor and questionnaire method, this paper investigated 344 students' chemistry values of grade 1 and grade 2 in a high school in Zhejiang, and compared the chemistry values of students of different sex, grades and choices to take examinations. The results showed that the metaphors of food students chose were plentiful up to 125 and the overall situation of students' chemistry values was relatively good. Chemistry values of boys and girls were almost same; the chemistry values of grade 1 students were more active than grade 2. As for students who chose to take different examinations, in general, students who chose to take an examination of chemistry had more active chemistry values, but students who didn't choose chemistry also had good impression on chemistry.

According to the shortages of flame reaction experiment in the textbook and based on the analysis of the principle and conditions of flame reaction, this paper designed four innovative experiments with wonderful phenomena, which successfully aroused students' interest in chemistry. What's more, the research developed the content of textbook and the educational function of chemistry experiment, making the classroom teaching more active and lively.

In copper-silver nitrate replacement reaction, it was usually observed that bright silver separated out on the surface of copper in water medium, but it was difficult to observe the shape of silver crystals. In order to see the morphology of silver crystals more clearly, this paper inquired the morphology and mechanism of silver precipitation under different media, temperature and concentration with agar and water as medium. The results showed that the silver was dendritic in agar and was flaky in solution, and the silver branch became variable and slender with the increase of temperature or the decrease of concentration in solution. The results could be explained by the three-dimensional network structure of agar and the screw dislocation growth mechanism of crystals.