Advanced Study Of "chemical Balance" Learning Based On ChemQuery Evaluation System

Science education is the main foundation of the dissemination of scientific knowledge and the innovation of science and technology,which plays a vital role in contemporary and future development.In recent decades,in the field of international science education,the study of learning progressions of core concepts has become a new research direction and hot point,which has not only gained a good foundation in the theoretical development,but also improved the measurement means to make this kind of research rise to a new level.The chemical equilibrium is an important component of the basic concepts and theories in middle school,so the article choose middle school chemistry core concept "chemical equilibrium" as the research object,on the basis of the knowledge ontology and equilibrium view in chemistry,curriculum standards,the version of senior middle school chemistry textbook and the basis of the existing related research.At the same time,using ChemQuery assessment system to classify chemistry equilibrium at learning progressions level,the hypothesis model of learning progression in chemistry equilibrium was constructed.ChemQuery assessment system is based on the core concepts in chemistry discipline framework,using the item response theory analysis of the standard reference,describing and measuring students understanding development of the core concepts,is a combination of qualitative and quantitative methods.It divides the level of students'conceptual understanding into five levels,followed by notion,recognition,formalization,construction and generation.The research is based on the established hypothesis model of learning progressions,and the measurement tools are compiled according to the corresponding level.In order to ensure that the measuring tools have good reliability and validity in the field measurement of large samples,the research firstly selects the senior high school students of an ordinary high school in handan city,hebei province as the subjects for the trial test.Winsteps software is used to analyze the test results and modify the measuring tools through the display results of various index parameters.Subsequently,the range of subjects was expanded for the second test,and it was found that the parameters of each indicator were within a reasonable range,and the reliability and validity of the measuring tool were guaranteed.Finally,the modified measuring tool was applied to the field measurement of large samples.The observed group of participants was selected from six different classes of three schools in handan,hebei province,yulin and ankang,shanxi province,who are students of grade 11 and grade 12.After the test,the collected large sample data were analyzed quantitatively and qualitatively by using Winsteps software,Excel software and so on,and the Measure value of each project and subject,white diagram and accuracy comparison chart were obtained.Study get the following conclusions:(1)Different grade students'understanding of the core concepts of chemical equilibrium significantly at different levels,including grade 11 students are mainly concentrated in level 2 and level 3,and grade 12 students are mainly concentrated in level 3 and level 4,so the grade 12 students overall understanding the concept of chemical equilibrium level higher than that of grade 11;(2)There are differences in the understanding of different sub-concepts among students of different grades,such as senior middle school students'understanding of the concept of "reversible reaction" "chemical reaction rate" has a small difference,but the understanding of the concept of "chemical equilibrium state" "direction and limit of chemical reaction" has a big difference.This paper,based on ChemQuery evaluation system,has the following implications and Suggestions for the follow-up research and teaching practice:(1)Learning progression promotes the rationalization of teaching strategies;(2)Learning progression promotes the optimization of curriculum design;(3)learning progression promotes the closeness of teaching objectives.At the same time,there are still some problems to be solved,which need more empirical studies to revise and improve.