以实验和论证为杠杆撬动化学概念深度学习——以“分子与原子”教学为例

Promoting Deep Learning of Chemical Concepts Through Experiments and Demonstration in Teaching of “Molecule and Atom”

以倡导"理解与批判、联系与构建、迁移与应用"的深度学习为理念,围绕"分子与原子的概念"比较教材与文献的设计思路,调整认知脉络,着力解决"概念学习过程中实验探究少,宏观现象进入微观分析的相关实验不匹配,忽略证据推理、变化观念与平衡思想核心素养"等不足。设计"3种形态的碘与淀粉的反应、H_(2)O_(2)溶液与品红反应、H_(2)O_(2)溶液的分解反应"3组实验,设置学生画分子模型、画H_(2)O_(2)分子分解的微观过程等活动,提炼"物质种类、分子种类、物质性质之间的关系是什么?你从实验中找到哪些证据支持观点?前2个单元的实验,还有哪些可作为论证的依据?"等问题,引发学生充分论证。"实验、活动、问题、论证"环环相扣,促成教学内容的有效结构化,通过化学概念的深度学习实现化学学科核心素养的发展。

With the idea of deep learning was to advocate "understanding and criticism, connection and construction, migration and application", around the "concepts of molecule and atom", compared the design ideas of teaching materials and literature, adjusted the cognitive line, putting efforts to solve problems such as "less inquiry experiment design, the macro-analysis and micro-analysis focused on different experiments, ignored chemical core literacy about evidential reasoning, change concept and balance though". Designed three experiments "the starch reacted with three forms of iodine union, the hydrogen peroxide solution was mixed with the magenta solution, the breakdown of hydrogen peroxide", planned activities "draw molecular models and sketches of the molecules of H_(2)O_(2) decomposition", raised questions "what is the relationship among species of matter, species of molecules, and properties of matter? what evidences did you find from experiments to support your view? ". Experiments, activities, questions and arguments were interlocking, built the structure of teaching content effectively, promoted students’ development from deep learning of chemical concepts to the chemical core literacy.