Research On Junior Middle School Students Developing Calculation Ability In Learning Chemistry

The science of chemistry is a subject of nature that studies the composition, the structure, the properties and the laws of change of matters on atomic and molecular levels. Qualitative study and quantitative study are two significant methods of study in the development of the science of chemistry, thus chemical calculation becomes an important part in chemistry. Chemical calculation in middle schools requests students to have a deeper understanding of chemical reactions, chemical concepts and chemical principles from the angle of quantitative study, to better grasp the properties and laws of change of matters, and to cultivate students’ abilities to analyze problems and solve problems with their knowledge of the science of chemistry.This paper probes into the teaching of chemical calculations in middle schools from the four aspects of the relative molecular masses, the calculation of relevant chemical formulas, the calculation of relevant chemical equations, and the calculation concerning solutions. The calculation of formulas includes the calculation of relative molecular masses, the calculation of the mass percentage of every element in chemical compounds, and the calculation of the mass percentage a certain element in chemical compounds. The calculation of equation includes the calculation of relevant reagents and products, the calculation of impurities and over-dosage. The calculation concerning solutions includes the calculation of solubility, the calculation of mass percentage of solutes in the solution, and the conversion between the solubility and the mass percentage of the solution.Here is the main way of study of the paper:Making the152students in Junior Three of SIQI Education, where the author is working, as the subject of study, and constructivism and problem-solving theory as the guiding principle, the author analyzes the traits of different kinds of chemical calculation and inquires the students about their problems of studying chemical calculations through questionnaires, designing all kinds of teaching processes of chemical calculation that comply with constructivism and problem-solving theory. Therefore, the teacher can help the students to be independently aware of the basic principles of chemical calculation, cultivate their abilities of independent thinking and calculating, develop their ability to think, to teach themselves and to solve problems, and discuss how to improve the students’ thinking of chemical calculation.Results show that chemical calculation should be done on the basis of a good understanding and grasp of relevant chemical knowledge and principles, and the clarified definitions of atoms, molecules and chemical formulas are necessities of chemical calculation. Therefore, we should base our teaching process of chemical calculation in middle schools on basic knowledge, closely connect the two points with each other, and improve our process on this basis. As to the chemistry teaching in schools, we should attach importance to basic knowledge so as to help students with regular solutions to problems, and to the training of skills so as to raise their skills to a higher level by seeking unique ways of solving problems. Study also shows that once we understand the basic principles of study and chemical calculation, design suitable teaching process, help them to be independently aware of the basic principles of chemical calculation and overcome their methods of cramming for chemical calculations, the students will study chemistry in a solid, flexible and efficient way.