| 类型：原创 | 来源：520化学网 | 作者/推荐人：化学教学与资源研究所 | 点击量：789859 | 时间：2012年6月5日 0:11:53 |
基于手持技术的酸碱中和反应学习的教学研究 专业：课程与教学论 申请者：黄碧芸 导师：钱扬义 摘 要“酸碱中和反应”是化学“学科关键词”(钱扬义，2009)，是教材必学的知识点，是师生教学与学习的重点，同时也是高考的热点。酸碱中和反应的内涵是酸和碱互相交换成分，生成盐和水的反应。这是酸碱中和反应概念的核心，其所包涵的外延多且广，涉及的主题有酸碱中和滴定、电解质、实验操作，还包括其他相关主题，如离子反应、电离平衡等知识。这些都是高中化学的核心概念，对于学生理解化学学科的基本原理具有重要作用，在教材和高考中具有举足轻重的地位。 手持技术是能够定量采集各种常见数据的并能与计算机连用的实验技术系统，具有操作简便、实验耗时短、直观性强和综合性高的优点。利用手持技术进行酸碱中和反应的探究，得到pH和电导率变化曲线，进而从氢离子浓度和溶液总离子浓度两个角度分析酸碱中和反应。 酸碱中和滴定教学是酸碱中和反应教学的重点。本研究以酸碱中和滴定为教学内容，利用手持技术作为教学手段，对师生的教与学做理论和实践的探究。 本研究主要分为五个部分。 第一部分对课题的研究背景、研究内容进行阐述，并提出研究的问题。本文所探讨的问题是，一线教师、职前教师和高中生是否接受手持技术引入酸碱中和反应教学中，并了解一线教师认为学生在传统课堂上学习酸碱中和反应上的难点是什么，手持技术能否解决该知识教学上的难点。实施基于手持技术的酸碱中和反应教学前后，高中生对知识的掌握程度如何变化？学习成绩如何变化？对自己的学习评价如何？ 第二部分是在对国内外的文献进行综述的基础上，了解手持技术与化学整合的概况。研究结果显示，国内外对手持技术的研究方兴未艾，国外偏向的是应用研究，国内由于是从国外引进的手持技术，一开始偏重的是理论研究，但最近几年也向应用研究发展；国外热衷于将手持技术应用在课堂教学中，并且关注学生使用手持技术的情况，以及如何发挥手持技术功效的策略等方面；国内涉及的较多是实验案例的开发，比较少关注手持技术运用在中学化学课堂中，而且比较少分析学生群体的情况。 第三部分是利用手持技术，采用pH传感器和电导率传感器测定强酸分别滴定强碱、弱碱和混碱，以及弱酸分别滴定强碱、弱碱和混碱的pH和电导率曲线，分析这六种反应方式的pH和电导率曲线变化的原因并总结特点和规律，有助于笔者把这些研究成果应用到实际教学之中，为教学提供科学的参考依据，促进学生对酸碱中和反应本质的理解。 第四部分是分别以一线教师、职前教师、学生为调查对象，以“手持技术”“酸碱中和滴定”为调查内容，调查施教者和学习者对手持技术引入酸碱中和滴定的态度及其他方面的看法，为第五部分的研究提供前期的实践指导。 调查研究1通过以结构式访谈为研究方法，调查一线化学教师认为传统课堂上学生在学习理解酸碱中和反应上的难点是什么，手持技术是否能解决该知识教学上的难点。研究发现，酸碱中和滴定实验涉及到的知识点比较多，包括了原理、操作、pH曲线、计算、终点判断、药品与仪器、电解质（强弱）、离子反应、电力平衡、盐类水解、数据分析、指示剂选择等，难点是滴定曲线的分析、数据计算、误差分析、操作注意事项和如何理解突跃范围等；手持技术有助于解决学习难点和提高学生的能力。 调查研究2采用问卷形式，调查职前教师接触手持技术的情况以及对手持技术引入酸碱中和反应的的认同感。研究发现手持技术在中学及大学的使用率都不是很高，职前教师通过自己动手实践利用手持技术探究酸碱中和反应，对手持技术有很好的认同感，认为将手持技术引入酸碱中和滴定实验是有意义的，并且愿意自己在将来的从教中使用手持技术实验。 调查研究3利用手持技术进行教学后，通过情感态度问卷和纸笔测试题，了解学生对手持技术引入教学的情感态度；以及他们对通过手持技术实验所传授的知识掌握情况。研究发现基于手持技术的高三复习课是一次有效有趣的教学，通过运用手持技术，在课堂中及时准确呈现出酸碱中和反应的电导率曲线，给学生一个感性的认知，结合分点分段分析电导率曲线的方法，使学生对酸碱中和反应有个全面的认识；手持实验使课堂变得生动活泼学生，比传统实验更轻松，学生可以更专注上课并喜欢老师用手持实验来辅助教学。 第五部分是在三个调查结果分析的基础上、在对教材和课程标准分析的基础上、在对高考题统计分析的基础上，结合基于手持技术探究酸碱中和反应实验，设计基于手持技术的酸碱中和滴定学习的教学设计，并与传统教学方式的教学效果进行对比。采用测试卷、评价表和访谈调查教学前后学生的知识理解的变化情况、学习效果评价的变化情况和情感态度情况。研究发现，基于手持技术的酸碱中和滴定pH曲线学习的教学比传统教学方式差异显著，前后成绩的提高比传统教学提高的多，有效提高学生宏观、微观和符号表征的能力，提升曲线表征与其他表征的转换能力；并且学生对自己的学习效果评价，不管是知识维度和技能维度，还是情感维度，都有明显的提高，学生接受并喜欢这种教学方式。 本研究一方面延伸了酸碱中和反应的实验研究、拓展了手持技术与化学整合的教学研究，对手持技术在课堂教学中应用的具有普适性和指导意义；另一方面突破高中化学学科难点、注重培养学生能力，为教师提供化学学科的教学案例辅助教学，并将相关资源放在“我爱你化学网”（http://www.520hx.com.cn/），对以后的手持技术教学研究具有理论和应用的双重价值。
关键词：手持技术 酸碱中和反应 pH 电导率 A TEACHING RESEARCH ON ACID-BASE NEUTRALIZATION REACTION BASED ON HANDHELD TECHNOLOGY Postgraduate: Huang Biyun Supervisor: Prof. Qian Yangyi Major: Curriculum and Teaching Theory ABSTRACT
"Acid-base neutralization reaction is a chemical" discipline "key words" (Qian Yangyi, 2009), is the knowledge of the textbook, the teaching and learning focus of the teachers and students in and the heat of the university entrance exam.The essential of acid-base neutralization reaction is the production of water by a component exchange process between acid and alkali. This essential is regarded as the core concept of acid-base neutralization reaction, and it has a wide-ranging of extensions which include not only acidbase titration, electrolyte, experiment operation, but also other related subjects such as ionic reaction and ionization equilibrium.These concepts are the core of senior school chemistry which may be able to help students understanding the chemistry elementary principle, and they are also have great effects on curriculum development and the college entrance examination. Handheld technology is an experimental technology system which can gather various kinds of common data and process data with computer. Its advantages are convenient operation, time-saving experiment, good intuition and high comprehensive. Researching acid-base neutralization reaction by using handheld technology, we can get a curve of electrical conductivity. As a result, acid-base neutralization reaction can be analyzed from two standpoints which are consistencies of hydrogen ion and solution. Acid-base neutralization titration experiment is the emphasis of acid-base neutralization reaction teaching. This project will consider acid-base neutralization titration as the teaching content. It will focus on researching the theory and practice about teaching-learning by teachers and students. There are five parts in this project. First part introduces the research background and research content, and raises questions in this project. The questions in this project are the following. If A-list teachers,pre-job teachers or high school students accept handheld technology using in acid-base neutralization reaction? What do think about the difficulty in studying acid-base neutralization reaction? Do teachers think can solve the difficulty of this learning by using handheld technology or not? What about’s situation of What about the students’ acceptance of handheld technology in acid-base neutralization reaction and their mastering of classroom learning. How is the students’ mastering status going after putting handheld technology into acid-base neutralization reaction teaching? How is the students’ academic record going? How do they evaluate their own learning situation? The second part is focused on the summary of integration between held technology and chemistry . It showed that the researching of held technology is on the rise at home and abroad. The research at abroad is biasing toward application research. The research at home is started with Importation of this technology from abroad and focus on researching theory. But it is start to be applied to classroom teaching at abroad at present. Moreover, it has been paid attention to the using by students and strategy about how it works better. The status of held technology is focus on experimental development. Handheld technology is devoted less attention to the application of it in teaching, and analysis of student group situation. The third part is a acid-base neutralization reaction experiment design based on handheld technology.More exactly, pH sensor and electrical conductivity sensor will be used to get the pH data and electrical conductivity curve of strong acid titration with strong alkali, weak alkali and Mixed-alkali respectively, and pH data and electrical conductivity curve of weak acid titration with strong alkali, weak alkali and Mixed-alkali respectively. After that, the pH data and electrical conductivity changing will be analyzed in these six chemical reactions. It will be used to apply this research to practical teaching. As a result, it can provide reference for the teaching and advancement of students’ perceptions. In this investigation, there will be an interview with A-list teachers, pro-job teachers and students. This interview is about handheld technology and acid-base neutralization titration. This investigation is about their opinions about Importation of handheld technology into acid-base neutralization titration, which is used for providing the guide in research. In Investigation one, the interview with A-list teachers is about what the difficulty in students’ understanding of acid-base neutralization titration and whether handheld technology can solve this difficulty in teaching or not. It showed that, acid-base neutralization titration experiment ranged over many subjects, included theory, pH curve, calculating, destination determination, medicaments, instrument, electrolyte, ionic reaction, electric balance, hydrolyzation, data analysis and indicator selection. The difficulty is the analysis of titration curve, data calculating, error analysis, operation points for attention and understanding the jumping range. Handheld technology can solve the learning difficulty and improve the students’ comprehension. In Investigation two, there will be a questionnaire. The investigation in this section is about status of using handheld technology be pro-job teachers and their acceptance of Importation of handheld technology into acid-base neutralization reaction. It shows that, the utilization rate of handheld technology is low in middle school and university teaching. The pro-job teachers research acid-base neutralization reaction by using handheld technology, and they think it is wonderful that Importation of handheld technology into acid-base neutralization reaction. And then they prefer to use this technology in their teaching in the future. In Investigation three, there will be a questionnaire about the emotion and attitude after using handheld technology in teaching. It will be used to learn about students’ emotion and attitude about Importation of handheld technology into teaching and their learning situation with handheld technology. It shows that, using handheld technology in review of senior years of high school is quite interesting. It can bring about perceptual-cognitive for students, which can combine with division and subsection analytical method of electrical conductivity. As a result, students can understand acid-base neutralization reaction overall. Handheld technology can make learning easily. Moreover, it can make students concentrate on learning and like learning by teaching with handheld technology. The fifth part is practical research. On the basis of investigation result analysis, analysis of teaching material, curriculum criterion and statistics of questions in college entrance exam, it combines with handheld technology in acid-base neutralization reaction experiment. As a result, I design an instructional design of learning acid-base neutralization titration base on handheld technology, and compare its effect with the traditional teaching. The investigation in this process is about students’ learning comprehension, learning effect and emotion how are going around investigation time. It shows that, there is a difference between using handheld technology in learning acid-base neutralization titration and learning acid-base neutralization titration with traditional teaching. The achievement of former was better than latter’s. Moreover, it can improve students’ representational capacity in macroscopic scale, microcosm and symbol, and improve students’ token ability in curve performance and other representational capacity. And then, the students set high value on their studying effect, improvement of learning and thinking. The students start to accept this teaching method and like this learning style. On the one hand, this project can extend the range of researching acid-base neutralization reaction experiment and expand the scope of combination between chemistry teaching and handheld technology. On the other hand, it can make headway on the problem of chemistry education in high school and put great emphasis on developing students’ ability. Moreover, it has theory value and using value, which can provide teachers with teaching assistance study in chemistry teaching.
KEY WORDS:handheld technology; acid-base neutralization reaction
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