Study On The Prototype Theory Be Applied In Teaching Chemical Symbol Of Ninth Grade Chemistry

Ninth grade chemistry is the initial stage for students to learn chemistry. In addition to cultivate students’interests to learn chemistry, it should also help them to develop the disciplinary thinking of chemistry study, which is on the basis of grasping the chemical symbols. However, it is difficult for ninth grade students to learn chemical symbols, so that the students give up learning chemistry gradually. Based on the Prototype Theory put forward by Rosch of the American psychologist in1975, and the "Macro-Micro-Symbol" Threefold Representation Theory of the chemistry, this research combines the cognitive characteristics of ninth grade students and the chemical symbols’teaching practice, and has a depth of theoretical and empirical research on ninth grade chemical symbols teaching. The result of the study provides theoretical and practical guidance for teaching of ninth grade chemical symbols.The author has been engaged chemical teaching of ninth grade for years, and know very well the students’chemistry study. This study has conducted the questionnaire survey, and summarized the status and problems in their chemical symbols’ learning. To solve students’ difficulties of facing chemical symbols learning, the author has made the literature research on the prototype theory, and found that the prototype theory that is based on "Family resemblance" is consistent with chemical science educational teaching mode. Besides, the use of the prototype theory in chemistry teaching can reveal chemical teaching principle. On this basis, the author has made the assumptions that the use of the prototype theory in chemical symbols teaching of ninth grade chemistry is very effective. What’s more, the experiment study of class teaching and case teaching proves that the prototype theory has a good instruction for chemical symbols teaching. The experiment study of class is found that the prototype theory plays a significant role in the chemical symbols teaching:teaching efficiency has greatly improved, especially, for middle-level students, their learning chemistry ability has been enhanced quickly in experiment class, there is very obvious difference in the scores of the posttest between experiment class and control class. Although the result of students with learning difficulties is not more satisfactory than that of middle-level students, the score is significantly higher than that of the control class.Using the prototype theory in chemical symbols teaching can reduce the difficulties of the students’learning chemical symbols has also been found through the study, enable students to study in a relaxed atmosphere while mastering the chemical symbols, and help them develop the specific chemistry thinking. On the whole, it has improved their learning chemistry ability, and indicates that there is a significant difference between experiment class and control class in the passing rate and excellent rate. Besides, case experiment study find that some different degree, using chemical symbols scheme under the guidance of the prototype theory can not only improve their chemistry learning ability, but also help them find the motivation and confidence in learning chemistry by intervening in chemical symbols learning for each individual in a short time. Furthermore, it is generally said that they clearly know the chemical knowledge better than before.In short, the use of the prototype theory in chemistry teaching of the ninth grade makes that teaching design is in accordance with the actual process of the students’learning chemical symbols, and has completely changed the situation that their psychological stress and learning burden is brought due to overemphasize rote and the mechanical memory of the chemical symbols in the traditional teaching.