A Comparative Study On "chemical Reaction Limit" PCK Of High School Chemistry Teachers

The professional development of chemistry teachers is inseparable from the development of subject teaching knowledge(PCK),which can be applied and embodied in teaching activities.Through the teacher's teaching process under the specific teaching theme,this paper analyzes some excellent PCK elements embodied by the teacher,which is helpful for the novice teacher to learn from in the teaching of this theme.This study in four different stages of development of a line of high school chemistry teachers as the research object,based on the perspective of PCK,characterization of the theme in the concrete teaching the limits of "chemical reaction" teaching process,the expert teachers and novice teachers,the concrete embodiment of each element of PCK,analysis and comparison,put forward to promote the new type chemical teachers' PCK development Suggestions under the specific topic.Through classroom observation method,interview method and text analysis method,based on the PCK under the specific subject of chemistry,this study is divided into 13 dimensions from five aspects of understanding knowledge of chemistry,knowledge of chemistry curriculum,knowledge of chemistry teaching method,knowledge of learners and knowledge of evaluation,and the following research results are obtained through in-depth analysis.As for the understanding knowledge of chemistry,the expert teacher can infiltrate it into the teaching of specific topics more than the novice teacher.In terms of chemistry curriculum knowledge,expert teachers are better than novice teachers in mastering the horizontal knowledge related to chemical reaction limits,but expert teachers and novice teachers have the same understanding of the position of chemical reaction limits in textbooks.As for the knowledge of chemical teaching method,expert teachers are more able to start from the perspective of students' learning than novice teachers.In terms of learner knowledge,novice teachers have a better understanding of wrong concepts than expert teachers.As for the evaluation knowledge,novice teachers will use more time to evaluate their own teaching.At the end of the paper,the following five Suggestions are proposed for novice chemistry teachers: to improve the understanding of chemistry;Good at analyzing the content characteristics of different chemical topics;Fully understand the situation,for teaching to lay a good foundation;Timely after-class reflection,constantly improve their own teaching;To strengthen the exchange of old and new teachers,learning teaching experience.