Observation And Evaluation Of Chemical Change In Senior High School Studengts Based On Rasch Model

The basic concept of chemistry refers to the holistic understanding of the chemical discipline formed by students based on their understanding and generalization of chemical knowledge.Under the guidance of the basic concept of chemistry,students can consciously use the unique thinking of chemistry to analyze the situation in any unfamiliar situation,and use the research methods of chemical science to solve problems.Chemical change is a core concept throughout chemical research.The concept of chemical change is one of the basic concepts of chemistry that middle school students should have,which is crucial to the development of the literacy of "change concept and balanced thought".At present,the research on the connotation,elements and evaluation of the concept of chemical change is still in the exploratory stage.Therefore,the evaluation of the chemical change concept is very important.Through literature analysis,the author sorts out the connotation and constituent elements of the concept of chemical change.The author believes that the concept of chemical change refers to the fact that students form a general understanding of chemical changes on the basis of in-depth understanding of chemical changes through the study of chemical change knowledge,and produce basic insights into substances and their changing phenomena.Specifically,it includes: the ontology of chemical change,the law view of chemical change process,and the value of chemical change.Furthermore,the author combined the high school chemistry textbook and the "General High School Chemistry Curriculum Standards(2017 Edition)"(hereinafter referred to as the curriculum standards),and preliminarily determined the evaluation scale based on the SOLO classification theory.According to the preliminary determination of the scale,the questionnaire was developed to investigate the development level of the chemical change concept of high school students,and then the Rasch model was used to analyze the initial test results,the questionnaire and evaluation index system were revised,and the optimized questionnaire was used to test the change concept of some high school students in two schools in Heilongjiang Province.Got the following result:1.The view of chemical change in high school students is at a high level,and students at level 2 and level 3 account for the majority.2.The development level of chemical change ontology and chemical change process law concept is high;the development level of chemical change values is low.3.The level of change view of key high school students is higher than that of ordinary high school students,the level of change view of boys is higher than that of girls,and the level of students with chemistry-related career tendencies is higher than that of students without relevant career tendencies,and the differences are significant.