Exploration Into The Conditions Of Learning "Applications Of The Amount-of-Substance In Calculation Of Chemical Reaction Equations"

Chemical calculation is an important course in the middle school chemistry and a basic skill for the students to learn the chemical change with the perspective of quantity. Researchers at home have studied the calculation methods and skills in the aspect of teaching, but it is still difficult that the students learn chemical calculation. Based on the constructivist learning theory, the research, with the experimental methods, attempts to find out the learning conditions for the students to apply the amount-of-substance to the reaction equation calculation so that it can supply a reliable teaching theory and highly effective teaching designs for the reaction equation calculation teaching of the middle school chemistry.In this paper, classifying the calculation learning of the middle school chemistry and investigating the reasons why it is so difficult for the students to learn chemical calculation have been done. Based on the studies mentioned above, the research have deviced the learning conditions of the amount-of-substance in the chemical equation calculation. The conditions are as follows: significance of reaction equation, relationships between the physical quantities, presentation Modes of the learning conditions, and the practice quantities after the learning.In this paper, with the study of teaching experiments, the influences of the conditions on the students' learning have been investigated. It shows that the above-mentioned conditions have the following influences on the application of learning the amount-of-substance to the reaction equation calculation:(l)The understanding of the significance of the reaction equation can have influence on the students' substantial command on the amount-of-substance in application of the calculation skills to thereaction equation calculation. In this stage, the students remain in the stage of imitation.(2) The concepts of physical quantities and the default of their mutual relationship affect that the students can not transplant the reaction equation calculation of the amount-of-substance into a new environment.(3) Not taking proper advantage of the pioneer organization in the process of learning impacts on the students' learning new knowledge and shaping the skills of chemical calculation.(4) Without consolidation of enough quantity practices, the students will be lack of preciseness and logicality when express and think over the chemical calculation, which couldn't contribute to the formation of the chemical calculation. The transplant ability of the amount-of-substance in the reaction equation calculation would be affected.