Research On The Concept Of Chemical Balance Based On RSM

Its vital important to understand the concept of chemical equilibrium which its thebasic concept of learning other concepts.Refer to the current research, the assessment ofstudents’ conceptual understanding still bases on the classical test theory,lacking oftargeted diagnostic evaluation. In this study,we apply the rule space model to evaluate thedegree of understanding the concept of chemical equilibrium, present individual andcollective diagnostic reports. Based on the above results,we develop remedial teachingstrategies and make relevant teaching suggestions.The assessment of understanding the concept of chemical equilibrium is based onmeasurement model-the Rule space model.Firstly, we define the meaning ofcomprehension and the conceptual comprehension by literature analysis and make asummary of conceptual understanding of relevant research.We draw aconclusion,understanding chemical equilibrium need three levels of representations, that ismacroscopic,submicroscopic and symbolic representation. Then we determine the level ofrelationship between the three properties,explain the meaning of triple representations inthe concept of chemical equilibrium.Simultaneously,we analysis the knowledge system ofchemical equilibrium concept in the textbook of Shandong Science and Technologyversion, reference to front-line senior teachers and subject experts opinions, that attributesmodel of chemical equilibrium contains five kinds of knowledge (reversible reaction,forward and reverse reaction rates, chemical equilibrium state, moving, chemicalequilibrium constants and conversion of chemical equilibrium) and logisticalrelationships.So chemical equilibrium model ultimately was constructed from twodimensions of cognitive properties that is the thought process attributes and knowledgecontent attributes.Secondly, according to the logistical relationships of cognitive properties of chemicalequilibrium model attributes, we test55kinds of ideal response patterns using Matlabsoftware program,so prepare items and arrang some students thinking aloud. Then encodethe item according to the properties the item examine, invite experts and high schoolteachers review, ultimately formed into a chemical equilibrium concept questionnairecontains24items to assessment the current understanding situation of chemicalequilibrium of150freshman students in the empirical research.Thirdly， we analyze the data processing. Because the items are in the form ofindefinite term multiple-choice, reducing speculation degrees, so we choose2PLM.We use ANOTE software to evaluate item difficulty b, discrimination a and capacity value θunder item response theory.we use Matlab software to calculate alert indicatorsanswer ζ which reflect students’ unusual circumstances,then establish (θ, ζ) space,123tobe classified point and the55pure rules point.Finally, the use of the minimumMahalanobis distance classified the123data, eventually100%of the subjects wereclassified as55pure rules point to a successful mode.Finally, reference to the feedback the provided attribution category, we developindividualized diagnostic reports and remediation strategies, then draw learning progressby Boolean algebraic analysis. Individual diagnostic report is used to teachindividualized,learning progress map can intuitive display the relationship between thestate of existing knowledge and the target state of knowledge, science teachers or studentscan develop remedial teaching or learning plan based on the learning path map. Meanwhile,for the difficults in the knowledge and building triple represents,we propose someteaching suggestions and practical examples,such as simulation experiment, microscopicmodel diagram, hand-held technology and multimedia technology and so on.Rule space model successfully applied in the evaluation of chemical equilibriumconcept provides a new method for assessment of chemical concept comprehension. At thesame time I hope to have more cognitive diagnosis model is applied to the field ofchemistry, breaking the limitations of traditional classical measurement theory, and richingassessment tools to help students diagnose cognitive processes for guiding teaching andlearning.