Construction And Teaching Design Of "Solution Acid And Alkaline" Learning In Middle School Chemistry

“The acidity and alkalinity of solutions” are distributed in different sections and units.It is the cornerstone of the basic theory of chemistry,and it run through the chemistry learning process of the whole middle school.Its related knowledge such as ionic reaction,water ionization,salt hydrolysis,etc.which are the key and difficult content of chemistry learning in middle school.The knowledge of the acidity and alkalinity of the solution is extensive and systematic,involving many concepts,complex reaction rules,Therefore,this part of the teaching has problems such as difficulty in constructing a knowledge system and many difficult concepts.Learning progressions is a new research field in the science education field in recent years.Through learning progressions descriptions of students at different levels of concept understanding at different levels of achievement,teachers can set teaching processes and teaching goals suitable for students' development,and help Students deepen their understanding of concepts.Construct the learning progressions of the acidity and alkalinity of the solution,test the cognitive level of students at different stages,understand the problems existing in the learning of this part of the content,and design teaching cases based on this.The content of the classroom teaching provides a reference.The research of this thesis first sorts out the relevant content of the advanced learning through literature retrieval,reviews the connotation,construction and research status of the advanced learning,and lays the theoretical foundation of the thesis.After literature search and interviews with teachers,the characteristics of the content of "solution acidity and alkalinity" and problems in teaching were determined.In order to present the knowledge structure system of the acidity and alkalinity of the solution clearly and clearly,the way of mind mapping is adopted.According to the "General Chemistry Curriculum Standards" and the chemistry textbook(People's Education Edition)to sort out the content of the acidity and alkalinity of the solution,the content of the acidity and alkalinity of the solution is divided into 5 levels,and the progress of the students at each stage is determined accordingly On the basis of the goal and the expected level,an advanced framework for learning the acidity and alkalinity of the solution is constructed.Prepare a questionnaire test based on the levels of the structured learning level to test the students' levels at different stages.Select the students of Senior One,Senior Two and Senior Three in the 11 th Middle School of Jiaozuo City as the survey objects,and use the obtained data to conduct the survey using SPSS 22.0.Data processing and analysis,to understand the cognition level of the acidity and alkalinity of the solution by the students of senior one,senior two and senior three.It is found that there is a significant difference in the third and third levels of high school and high school students,and there are significant differences in the fourth and fifth level of high school and high school students.According to the conclusions of the above studies,the related contents of the acidity and alkalinity of the solutions related to the freshman and high school were designed,the teaching situation was designed,and the starting level and the advanced goal were determined according to the constructed advanced learning framework,and the test was evaluated.The problems existing in the first and second high school students are emphasized in teaching,so that students can master the knowledge in problem solving,with a view to providing reference for the teaching practice of acid and alkali related content of solutions.