Research On The Problem Obstacle And Teaching Strategy Of Chemistry Comprehensive Calculation For Junior High School Students

Junior middle school is the enlightening stage of chemistry learning.It is not only necessary to cultivate students' interest in learning and let them preliminarily learn to understand the world by means of chemistry,but also to cultivate their basic quality of chemistry and scientific concept of material and change.Chemistry learning from qualitative to quantitative,higher level learning and research are inseparable from the learning of chemical calculation,especially the comprehensive calculation of the fusion of chemical change situation.In the actual teaching,it is found that the students' comprehensive ability to solve computational problems is weak,and they are prone to fear of difficulty,which affects the connection of chemistry learning between junior high school and senior high school.Combined with my own experience and literature research,the psychological mechanism of solving chemical comprehensive calculation problem is found that the solution of chemical comprehensive calculation problem is firstly based on a certain chemical declarative knowledge and procedural knowledge system.The problem solving process of chemical comprehensive calculation can be divided into five stages: identifying problems,analyzing problems,finding solutions,implementing solutions,checking,reviewing and evaluating solutions.During the process,students may have problem solving,cognitive disorder,dyscalculia,thinking disorder and psychological disorder.According to the behavior of these types of disorders,the corresponding questions were set in the questionnaire for comprehensive computational problem solving disorders of junior high school students.A total of 134 students from 8,9,10 classes of junior high school teachers were investigated.Then five students were selected and interviewed from five aspects,namely,students' interest in comprehensive computing learning,difficulties encountered,methods of dealing with wrong questions,and the analysis of specific problem-solving ideas of some concepts and principles,so as to have a deeper understanding of their real situation in solving comprehensive computing problems.Survey analysis found that: 1.The early stage of the integrated computation teaching students recognition and analysis of the problems is the key problem,students must pass the chemistry language structures,correct problem situation,the recommended students through the graphic method on the analysis of the problem situation and understanding,and dismantling the key steps to solve the problem,to help students to build confidence through different questions and ability training again how to find the key of the quality of the pure substance to the calculation,for solutions,forming a complete experience of problem solving.2.Basic knowledge of chemistry restricts students' identification and analysis of problems,and students who often encounter obstacles are more likely to be afraid of difficulties.Attention should be paid to supervise students' implementation of basic knowledge in teaching.Including chemical symbols,relative molecular weights,the meaning of chemical equations,the law of conservation of mass and simple calculation of chemical equations,as well as solute,solution analysis,solute mass fraction,these concepts and principles of teaching.Help students to organize and memorize chemical knowledge in a scientific way,such as making mind maps by hand when reviewing each unit,and help students to build a basic knowledge system.3.Most of the students lack of independent thinking and reflection ability,hope that the students and the teacher's help,not through the analysis of their own to find methods,accumulate experience,so when they have a problem,not according to the effective information,the formation of reactive,in the long term answer long time consuming,effect,problem solving ability is weak,the difference with other students.4.Many students do not have the consciousness of checking and reviewing after answering the questions,and often make mistakes in writing chemical equations and calculating relative molecular weight,which affects the solution effect.It is suggested that students sort out the wrong questions regularly.The teacher emphasizes the standardization of the answers in the teaching of simple calculation of chemical equations,and the importance of checking after answering the answers.Students should develop a rigorous habit from the very beginning.After the implementation of the teaching strategy,the scores of students in the simulation examination of high school with different difficulties were calculated comprehensively.The overall score rate was improved compared with that before,and the gapwith the average grade level was narrowed,indicating that the teaching strategy had certain effects.