“电离平衡”学习难点成因分析与教学策略研究

发布时间：2018-12-15 00:31

【摘要】：“电离平衡”是高中化学阶段的重要内容,在高中化学知识网络中是重点也是难点。新的教材编排体系注重知识的螺旋式的上升和多层面的呈现,力求更好的学习效果。这一单元内容系统性较强、学习要求弹性很大,概念性、核心性、理论性、综合性都较强,涵盖的知识面丰富、考察方式较灵活,对思维能力的要求很高,恰恰也是学生难以理解的微观抽象的理论知识。电解质溶液体系一般有几个可逆反应,共同处于矛盾统一体中,相互影响,相互制约。学生抽象概念的形成、建模的思想和整体的思想还不成熟,学生的思维从宏观到微观的转变显得有些困难。所以这一模块内容是学生学习时的难点,也使教师教学的难度加大。学习中的难点可能会变成学生学习的分化点,处理好教材和学习中的难点是优化化学教学及提高学生学习效率的关键环节。如果采取有效的措施突破学习难点,将有利于培养学生的创新意识和化学素养、开发学生智力、内化各种能力、并帮助学生形成化学思想。本研究通过系统的理论分析,以湖北省武昌实验中学高二的2个普通班和2个实验班的学生为研究对象,采用文献分析法、问卷调查法、访谈法,对高中化学选修4“电离平衡”单元中的难点进行实证研究,调查学生对电离平衡知识的理解情况,对学生知识测验结果进行分析归纳,找出学生在学习过程中思维跳跃较大或阻力较大的难点,通过理论研究深入分析,并找出学习难点形成的原因,最后根据理论指导实践的原则,在分析调查结论的基础上结合教学实践提出突破难点的教学策略。经过调查分析和访谈,本研究得出如下结论：电离知识的难点均在于未能深入理解基本概念与原理的实质,学生能够运用基本知识解决简单的化学问题,知识的综合运用存在障碍,知识的迁移运用能力和问题表征能力不足。“电离平衡”单元学习内容中难点形成的主要原因在于缺乏有效的、针对性的化学认知策略；个体身心发展阶段性存在一定的局限；学生思维定势的消极影响；化学认知结构存在缺陷；知识的储备量少,结构化程度低；知识的表征不完善,使知识变得僵化；问题表征的能力差以及学生头脑中前科学概念干扰知识的构建。针对“电离平衡”单元学习内容中的难点提出以下教学策略：整体把握教材,找准知识逻辑顺序；立足学生认知,注重知识形成过程；丰富学生感性认识,设置认知变式问题,优化学生的认知策略；发展学生思维,促进知识正向迁移；改变教学方法,促进学习难点的突破。
[Abstract]:Ionization equilibrium is an important part of high school chemistry, and it is a key and difficult point in high school chemistry knowledge network. The new textbook arrangement system pays attention to the spiral of knowledge and the presentation of multiple levels in order to achieve better learning effect. The content of this unit is relatively systematic, the learning requirements are very flexible, conceptual, core, theoretical, and comprehensive, covering a wide range of knowledge, more flexible inspection methods, and very high requirements for thinking ability. Is precisely the student is difficult to understand the micro-abstract theoretical knowledge. There are several reversible reactions in electrolyte solution system, which are in contradictory unity, influence and restrict each other. The formation of abstract concept, the idea of modeling and the whole thought are not mature, so it is difficult for students to change their thinking from macro to micro. Therefore, the content of this module is difficult for students to learn, and makes it more difficult for teachers to teach. The difficulty in learning may become the differentiation point of students' learning. It is the key link to optimize chemistry teaching and improve the efficiency of students' study to deal with the teaching materials and the difficulties in learning well. If effective measures are taken to break through the learning difficulties, it will be beneficial to cultivate students' innovative consciousness and chemical literacy, develop students' intelligence, internalize various abilities, and help students form chemical thoughts. Through systematic theoretical analysis, this study takes the students of two ordinary classes and two experimental classes in Wuchang Experimental Middle School in Hubei Province as the research objects, and adopts the methods of literature analysis, questionnaire investigation and interview. This paper makes an empirical study on the difficulties in the 4 "ionization equilibrium" unit of chemistry elective course in senior high school, investigates the students' understanding of ionization equilibrium knowledge, and analyzes and summarizes the results of the students' knowledge test. This paper finds out the difficulty of students' thinking jump or resistance in the process of learning, analyzes deeply through theoretical research, and finds out the reasons for the formation of learning difficulties. Finally, according to the principle of guiding practice in theory, On the basis of analyzing the investigation conclusion, combining with teaching practice, the paper puts forward some teaching strategies to break through the difficulties. Through investigation, analysis and interviews, this study draws the following conclusions: the difficulty of ionization knowledge lies in not deeply understanding the essence of basic concepts and principles, and students can use basic knowledge to solve simple chemical problems. There are obstacles in the comprehensive application of knowledge, the ability of transfer and application of knowledge and the ability of problem representation are insufficient. The main reasons for the difficulties in the study of "ionization balance" unit are the lack of effective and targeted chemical cognitive strategies, the limitations of the stages of individual physical and mental development, the negative influence of students' thinking patterns, and the following aspects: (1) the main reasons for the formation of difficulties in "ionization balance" units; There are some defects in the structure of chemical cognition; the storage of knowledge is small and the degree of structurization is low; the representation of knowledge is imperfect, which makes knowledge become rigid; the ability of problem representation and the prescientific concepts in students' minds interfere with the construction of knowledge. In view of the difficulties in the study of "ionization balance" unit, the following teaching strategies are put forward: grasp the teaching material as a whole, find the logical sequence of knowledge, base on students' cognition and pay attention to the process of knowledge formation; Enrich students' perceptual knowledge, set up cognitive variant problems, optimize students' cognitive strategies, develop students' thinking, promote positive transfer of knowledge, change teaching methods and promote the breakthrough of learning difficulties.
【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2012
【分类号】：O6-4;G642.4

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