A Study On Modeling Teaching For Halogenated Hydrocarbon Of Chemistry In Senior High School

The model cognition in chemical discipline core literacy is committed to developing thinking and ability of students' cognition for substance,which is paid more and more attention in chemical education of secondary school.The modeling teaching is an important way to develop model cognitive ability.The halogenated hydrocarbon,an important organic compound but rarely found in nature,is a kind of intermediate substances for synthesizing many important organic compounds,and plays an important role in the reaction of synthetic materials.Therefore,halogenated hydrocarbon plays a vital role in the teaching of organic chemistry in senior high school.In addition,model methods and thinking have been applied to classroom teaching in domestic and foreign teaching researches.However,it has not been used in the teaching of halogenated hydrocarbon,and there are few researches on the modeling teaching of knowledge system for organic compounds.Through the modeling teaching of the halogenated hydrocarbon in chemistry teaching,this thesis provides the general law of learning organic chemistry and cultivates the cognitive ability of students on model construction and halogenated hydrocarbon knowledge.Firstly,this thesis summarized the teaching of organic chemistry in senior high school and the teaching of chemical modeling in secondary school.Taking zone of proximal development and constructivism theory as the background,and designed the questionnaire of investigation on current situation of modeling teaching in organic chemistry knowledge classroom in senior high school,which was used for testing students' learning attitude and method of organic chemistry knowledge,and their cognition degree and application consciousness of modeling.Meanwhile,the chemistry teacher interview in senior high school was carried out in order to understand the application status of chemical modeling teaching in secondary school.After that,teacher builds a bridge to learn new knowledge based on the existing knowledge and experience of students,and a teaching model of “situation-experiment-induction-cognition” for halogenated hydrocarbon was proposed,that is,using halogenated hydrocarbon's situations to press close to real life and the properties of bromoethane are deepened by experimental models.Then the teacher summarizes the concept and properties of halogenated hydrocarbon,and guides students to master the method of learning organic compounds from individual inductive reasoning to the whole,which could improve students' cognitive ability of halogenated hydrocarbon knowledge and thinking mode of establishing and applying models.Secondly,based on the constructed “situation-experiment-induction-cognition”model,teacher designed the teaching link and carried out the teaching practice,then advanced the teaching contents step by step and explored the nature of knowledge through modeling teaching.The structure and characteristics of typical individuals were summarized into the characteristics of the common things.The results of examination paper survey were statistically analyzed to evaluate the effect of the modeling teaching.Practice has proved that the application of modeling teaching for halogenated hydrocarbon in senior high school is effective,which is helpful for students to build knowledge system of halogenated hydrocarbon,master the general law of learning organic chemistry,promote the cognitive development of modeling thinking,and improve the ability to solve practical problems.The results of the teaching reform are conducive to promoting the diversified choices of chemistry teachers designing teaching link and mode in senior high school,which is expected to provide a feasible scheme for the teaching method of halogenated hydrocarbon.