Senion Students’ Mental Model Of Chemical Triple Representation In Chemical Reaction

Chemical triple representation was brought forward by Johnston Professor of Scienceand Education Center of the University of Glasgow, Scotland. After30years ofdevelopment, triple representation has gradually become one of the most influential andmost creative thinkings. Gilbert and Treagust point out that triple representation hasbecome the theoretical basis of the chemical education research, guiding the works of thechemistry teachers and the curriculum developer around the world. Chemical triplerepresentation is so important that chemistry learning must from macro, micro and symbollevels, and then mental model of the chemical triple representation was devolped inlearners’ mind. Understand the mental models of the chemical triple representation wouldhelp teachers and curriculum to understand the students difficulties in learning. Becauseoxidation-reduction reaction is not only a core concept in high school chemistry learning,but also one of the most difficult concepts in students’ learning, it was chosed to research.Based on the literature review, the research theory and main views were broughtforward. The chemical triple representation is not only the external presentation of thechemical knowledges in macro world, the microscopic world and the symbolic world, alsotheir reflection in mind. Mental model is not only the knowledge scheme in mind, also adynamic internal operation mechanism affecting the individual’ describing, explaining andpredictting of the external things. The mental model of chemical triple characterization isthe knowledge scheme in mind after representing the chemical concept or knoeledge frommacro-micrl-symbol levels, affecting the individual’ describing, explaining and predicttingof the external things. One’s mental model is diffrent from others, and it is imperfect ingeneral.It will be improved constantly with the ongoing school education.Our empirical study consists of two parts.One is the development of aquestionnaire,the other is the investigation to senior middle school students onoxidation-reduction reaction by the use of questionnaires.The conclusion are those:1.There are many different mental models in the Senior middle school students indifferent grades.There are elevern mental models in the first grade of senior high school,nine in the second grade and four in the third grade. Almost all the students’are good atthe symbol represention. The law of conservation of mass, the valence, the relationshipbetween the valence and the pros and cons of electronic are difficult to students.2.The development of the mental models in senior middle school students f isgradual.Firstly, the higher of the grade,the less of the wrong model types and the people,the more of the people in the scientific model.Secondly, students in grade one of the senior middle school prefer electronic model, sequence model and valence model, students ingrade two prefer valence mdel, and students in grade three prefer scientific model.Thirdly,although studengts in grade one of the senior middle school have scientific model, thatdoes not mean that other models should disappear.It is same even to the studengts in gradeone of the senior middle school. That indicates that the development of the student’smental models is incremental, rather than revolutionary.3.The mental models of the senior middle school students are instability.The sudents’answeer is largely limited to the form of the question. If the problem is in the form of atwo-stage diagnostic question,the students tend to choose a scientific model.If the problemis in the form of semi-structured interviews, students use their own preference mentalmodel to answer questions.The higher of the grade, the more scientific of the student’smental model, the smaller the degree of contextual interference. Overall, the mental modelsof all the senior middle school students are situational dependent and unstable.4. The degree of consistency of the mental models of excellent students and studentswith learning difficulties is different.The more scientific of mental model, the higher of thedegree of consistency. When answering the questions,students in grade one of the seniormiddle school use more mental models than other grades.The higher of the grade,the less ofthe mental models used.Then the conclusion was draw.5. Elements influencing the mental model are different to different grades. There arefour elements affects students’ mental model in grade10, two elements affects students ingrade11and none for students in grade12.6.The difference between excellent students and students with learning difficultiesmainly lies in the microscopic represention.If students understand the chemical conceptionbased on the micro nature, the mental model would be scientific, the scores in the wholequestionnaire would be higher, the conversion capacity among the thriple representionwould be relatively strong. If students understand the chemical conception don’t base onthe micro nature, the performance would be worse.There are three innovations. The first one is the formation of a good questionnaire.The second is that11mental models are proposed systemly and they are Verified. The thirdis that the distribution and characteristics of these mental models are analyzed, and the keyelement causes the students different is analyzed too.