溴乙烷的取代反应和消去反应的实验探究--喻亚琴

溴乙烷的取代反应和消去反应的实验探究--喻亚琴 “溴乙烷的取代反应和消去反应的实验探究”教学设计 广州市玉岩中学 喻亚琴 一、教学内容主线分析 (1)《普通高中化学课程标准(实验)》中对本单元的学习提出如下要求和活动探究建议:?认识卤代烃典型代表物的组成和结构特点。?知道卤代烃与其他有机化合物之间的转化关系。?根据有机化合物组成和结构的特点，认识消去反应。?用化学 方法 快递客服问题件处理详细方法山木方法pdf计算方法pdf华与华方法下载八字理论方法下载 (或红外光谱法)检验卤代烃中的卤素。?调查与讨论:卤代烃在生产生活中的应用，以及对健康的危害。 (2)卤代烃在天然有机化合物中存在极少，自然界中存在的卤代烃几乎都来源于人工合成。卤代烃是有机合成中的重要试剂，常用来提供碳正离子，而卤代烃与金属镁形成的格氏试剂又是常见的提供碳负离子的试剂，所以卤代烃在有机合成中占有极其重要的地位。 (3)卤代烃既是核心基础知识的直接体现，又是合成其他有机物的桥梁和纽带，研究卤代烃，能够帮助学生从整体上综合认识有机化学。 (4)消去反应使学生新接触到的一个反应类型，学好这个反应，就为醇的消去反应打好了基础，掌握消去反应对反应物的结构特点要求(只有连接卤原子的碳的邻碳上连接有氢原子)，还有对消去的不同产物的判断。 (5)虽然卤代烃与烃类的结构差别不大，但是卤代烃的化学性质却与相应的烃的化学性质存在较大区别，这个事实可以让学生进一步加深对结构决定性质这一重要化学思想的认识。通过对溴乙烷在氢氧化钠水溶液或氢氧化钠乙醇溶液两种不同条件下所发生反应的观察与思考，让学生学习卤代烃化学性质的同时，通过对比的方法认识有机化学的重要反应——消去反应。在深刻思考相同反应物在不同反应条件下可发生不同反应的基础上，充分认识有机化学反应条件的重要性，从而引导学生全面把握有机化学反应规律。 二、学情分析 由于在必修化学的学习阶段学生对具体的有机化合物(如甲烷、乙烯、苯、乙醇、乙醛、乙酸等)只是有了一些感性认识，在本模块第一章中学习了有机化合物的结构、分类、命名等一些概念，所以对某些较抽象或规律性的有机化学基本知识，如有机物中碳原子的成键特点、有机物结构的表示方法、同分异构体的识别等内容只是有所了解，并没有理解到位。根据学生已有知识基础看，学生对本节学习的主要困难在于溴乙烷的结构特点和主要化学性质和卤代烃水解和消去反应，尤其是条件不同、产物不同的理解和分析(氢氧化钠的水溶液为水解，而氢氧化钠的醇溶液为消去)和消去反应对反应物的要求;而本课时难点在于不同条件下的产物分析和检验。 lujianhua (South area ahead Office Director and to war victory)]. County Government operates 3 Civil Affairs, finance, education and Finance Committee, with espionage, sabotage, standing and political team. Soon, the tomb of the Wujiang District Committee of the Kuomintang relocated to the countryside village. Pre-war, strict tomb for seventh district, its regional range for this Taoyuan town and town of Nan Ma Street, and Tan Qiu street of rotten Brook Tang West of area, in Wujiang South border, and Zhejiang Province Tongxiang County, and Wuxing County adjacent, ancient for two province (River, and Zhejiang) three House (Suzhou, and huzhou, and jiaxing) seven County (wuxing, and return Ann, and Tongxiang, and jiaxing, and show water, and Wujiang, and earthquake Ze) of make, is located in remote, territory size Lake swing dotted, river port criss-cross, easy hidden combat, and no Highway, traffic inconvenience. Therefore, this has become the refuge of many, where Wujiang gentleman most of the refuge is not the fall of four townships, at this time of grave, there has been a monstrous prosperity, Nanxun town, even the neighboring Zhejiang Province, there are also some merchants to Yan Tao DUN Cun opened shop. Cang during the depression as a regional political center and military base in the area. In May 1938, Chairman Mao Zedong in the guerrilla war in the strategic issues of: "North zone, South of the Lake of hongze Lake area branching stream of all enemy-occupied areas and along the coastal areas, should be well organized guerrilla and in rivers, lakes and estuaries and build lasting base nearby, as one aspect of the development of the national guerrilla". 三、教学目标 1、知识与技能: (1)掌握溴乙烷的主要化学性质，理解水解反应和消去反应. (2)掌握检验不同反应的产物方法，能根据结果设计实验方法检验产物。 2、过程与方法: (1)分析有关卤代烃所发生的化学反应的类型的和反应条件，树立”条件不同，反应不同的“化学思想。 (2)通过对实验的探究，培养学生发现问题、解决问题的能力。 (3)学生的学习策略是实验探究、实验现象的分析和讨论为主。 3、情感态度价值观: (1)通过学生的实验探究活动，理解科学的严谨性、创新性，培养学生一丝不苟的学习态度和创新精神。 (2)通过分组设计实验，培养学生协作，相互交流的能力。 四、重点、难点分析 【教学重点】 1.溴乙烷的水解和消去反应 2.不同条件下卤代烃产物的检验 【教学难点】 不同反应条件下卤代烃产物的检验 五、教学过程 教学环教师活动 学生活动 设计意 节 图 【复习引入】溴乙烷的水解回忆、 书 关于书的成语关于读书的排比句社区图书漂流公约怎么写关于读书的小报汉书pdf 写方程式 利用两 反应方程式，溴乙烷的消去 个复习 反应方程式(强调条件) 方程式导入新快速浏览学生书写 引入新课 【投影】学生答案 自我 评价 LEC评价法下载LEC评价法下载评价量规免费下载学院评价表文档下载学院评价表文档下载 书写结果 课。检查 学生上 节课掌 握情况lujianhua (South area ahead Office Director and to war victory)]. County Government operates 3 Civil Affairs, finance, education and Finance Committee, with espionage, sabotage, standing and political team. Soon, the tomb of the Wujiang District Committee of the Kuomintang relocated to the countryside village. Pre-war, strict tomb for seventh district, its regional range for this Taoyuan town and town of Nan Ma Street, and Tan Qiu street of rotten Brook Tang West of area, in Wujiang South border, and Zhejiang Province Tongxiang County, and Wuxing County adjacent, ancient for two province (River, and Zhejiang) three House (Suzhou, and huzhou, and jiaxing) seven County (wuxing, and return Ann, and Tongxiang, and jiaxing, and show water, and Wujiang, and earthquake Ze) of make, is located in remote, territory size Lake swing dotted, river port criss-cross, easy hidden combat, and no Highway, traffic inconvenience. Therefore, this has become the refuge of many, where Wujiang gentleman most of the refuge is not the fall of four townships, at this time of grave, there has been a monstrous prosperity, Nanxun town, even the neighboring Zhejiang Province, there are also some merchants to Yan Tao DUN Cun opened shop. Cang during the depression as a regional political center and military base in the area. In May 1938, Chairman Mao Zedong in the guerrilla war in the strategic issues of: "North zone, South of the Lake of hongze Lake area branching stream of all enemy-occupied areas and along the coastal areas, should be well organized guerrilla and in rivers, lakes and estuaries and build lasting base nearby, as one aspect of the development of the national guerrilla". (尤其 是反应 条件)， 为新课 知识做 准备。 【过渡】昨天课后有同学问通过实 我，你怎么知道它们的产物 验设置， 溴乙烷是谁,今天我们就一起来探 引导学 的水解究产物。 生分析 反应 【实验探究】1、请你设计一讨论交流，可能答案:1、取少量溶液溴乙烷 个实验证明溴乙烷的Br变与新制氯水反应，有红棕色液体产生，的水解 --成Br, 证明原来有Br。2、加入硝酸银溶液，反应，通 有淡黄色沉淀AgBr产生。过学生 2、如何证实水解产生了乙乙醇的检验可以用酸性高锰酸钾溶自我发 醇, 液检验。 现问题 【实验操作】根据提出的方动手实验 设计方 案 案，实践 快速巡查，观察学生实验动【发现问题】1、直接加硝酸银溶液中不断 态，引导学生发现问题。 现象不明显，有褐色沉淀，看不到预改进方 测的现象。2、高锰酸钾溶液不褪色或 案，最终 者现象不明显。3、溴乙烷挥发 解决问 题，培养 【问题探究】为什么会有褐思考、回答:溶液中有氢氧化钠，能学生科 色沉淀,(提示:考虑溶液与硝酸银反应得到AgO暗褐色沉淀，学探究2 -成分) 对Br的检验产生干扰。 的能力， 溴乙烷与氢氧化钠水溶液振荡混合激发学 如何避免, 后加热，持续时间段，可采用水浴加生学习 热。待溶液静置后，用滴管吸取少量化学的 he La-".asting base nearby, as one aspect of the development of the national guerrillaoccupied areas and along the coastal areas, should be well organized guerrilla and in rivers, lakes and estuaries and build l-ke of hongze Lake area branching stream of all enemyy base in the area. In May 1938, Chairman Mao Zedong in the guerrilla war in the strategic issues of: "North zone, South of tare also some merchants to Yan Tao DUN Cun opened shop. Cang during the depression as a regional political center and militar there townships, at this time of grave, there has been a monstrous prosperity, Nanxun town, even the neighboring Zhejiang Province,nvenience. Therefore, this has become the refuge of many, where Wujiang gentleman most of the refuge is not the fall of four cross, easy hidden combat, and no Highway, traffic inco-e, is located in remote, territory size Lake swing dotted, river port crissing) seven County (wuxing, and return Ann, and Tongxiang, and jiaxing, and show water, and Wujiang, and earthquake Ze) of makd jiaxgxiang County, and Wuxing County adjacent, ancient for two province (River, and Zhejiang) three House (Suzhou, and huzhou, anwn of Nan Ma Street, and Tan Qiu street of rotten Brook Tang West of area, in Wujiang South border, and Zhejiang Province Tonwar, strict tomb for seventh district, its regional range for this Taoyuan town and to-ng relocated to the countryside village. Prettee, with espionage, sabotage, standing and political team. Soon, the tomb of the Wujiang District Committee of the Kuomintaion and Finance Commilujianhua (South area ahead Office Director and to war victory)]. County Government operates 3 Civil Affairs, finance, educat 3 - 上层清液，移入另一盛稀硝酸的试管兴趣。 中，然后滴入2,3滴硝酸银溶液，如 - 有淡黄色沉淀出现，则证明含有Br 【解释】乙醇量太少，高锰 酸钾溶液褪色不明显，因此用核磁共振氢谱或者红外来检验乙根据已 可以用其他波谱方法来检醇。 有知识 验，比如, 推导到 【改进检测】 改进后进行检测，能看到淡黄色沉类似物 【提升】根据今天的实验，淀。 质上，培 如何检验卤代烃中卤素原子思考、迁移:利用氢氧化钠的水溶液养学生 呢, 进行水解反应，将卤素原子转化为卤迁移能 素离子，加硝酸酸化，后加硝酸银溶力。 液，产生白色沉淀是氯化银，黄色沉 淀是碘化银。 溴乙烷【过渡】条件不同，反应结 指导学 的消去果就不同。当我们把氢氧化 生学会 反应 钠的水溶液改成氢氧化钠的 对比反 乙醇溶液，就会发生另外一 应条件， 个反应。 并根据 【问题探究】1、产生的乙烯回答:将气体通入酸性高锰酸钾溶液已有知 可以用什么方法检验, 或者溴水(溴的CCl4溶液)中，看识来指 能否褪色。 导实践 2、为什么要在气体通入酸性除去挥发出来的乙醇，它也能使酸性活动。 高锰酸钾溶液前加一个盛水高锰酸钾溶液褪色。 培养学 的试管,它起什么作用, 生根据 3、如果改成溴水(或者溴的不用，它们不会使溴水(或者溴的CCl要求设4 CCl4溶液)，还有必要将气溶液)褪色。 计实验 方案 气瓶 现场处置方案 .pdf气瓶 现场处置方案 .doc见习基地管理方案.doc关于群访事件的化解方案建筑工地扬尘治理专项方案下载 的体通入水中, 【设计】分组设计实验装置，思考、动笔设计实验装置图，并画出能力，并 lujianhua (South area ahead Office Director and to war victory)]. County Government operates 3 Civil Affairs, finance, education and Finance Committee, with espionage, sabotage, standing and political team. Soon, the tomb of the Wujiang District Committee of the Kuomintang relocated to the countryside village. Pre-war, strict tomb for seventh district, its regional range for this Taoyuan town and town of Nan Ma Street, and Tan Qiu street of rotten Brook Tang West of area, in Wujiang South border, and Zhejiang Province Tongxiang County, and Wuxing County adjacent, ancient for two province (River, and Zhejiang) three House (Suzhou, and huzhou, and jiaxing) seven County (wuxing, and return Ann, and Tongxiang, and jiaxing, and show water, and Wujiang, and earthquake Ze) of make, is located in remote, territory size Lake swing dotted, river port criss-cross, easy hidden combat, and no Highway, traffic inconvenience. Therefore, this has become the refuge of many, where Wujiang gentleman most of the refuge is not the fall of four townships, at this time of grave, there has been a monstrous prosperity, Nanxun town, even the neighboring Zhejiang Province, there are also some merchants to Yan Tao DUN Cun opened shop. Cang during the depression as a regional political center and military base in the area. In May 1938, Chairman Mao Zedong in the guerrilla war in the strategic issues of: "North zone, South of the Lake of hongze Lake area branching stream of all enemy-occupied areas and along the coastal areas, should be well organized guerrilla and in rivers, lakes and estuaries and build lasting base nearby, as one aspect of the development of the national guerrilla". 投影出可能用到的仪器的画初稿。 通过动 法 手实验， 激发学 【投影】选择部分学生图片， 参与评价，修改自己的设计图。 习化学 热情。 练习和【投影】1、要证明氯乙烷中练习 强化巩迁移 氯元素的存在可以进行如下固所学 操作，其中顺序正确的是() 知识 ? 加入AgNO溶液?加入3 NaOH溶液?加热?加 蒸馏水?冷却后加入硝 酸酸化?加入NaOH的 乙醇溶液 A、???? B、???? C、??? D、??? 教学反思:本节课的重点在于突破卤代烃的卤素原子鉴别，采用实验探究的方式。本节内容是具有一定难度要求的，学生比较难以回答。但是如果采用设计梯度问题:?溴乙烷的水解反应方程式是怎样的(强调书写反应条件),这样学生通过书写回顾了水解反应，根据方程式能判断反应前后Br的存在形式。这时候过渡到第二个问题就自然简单。?请你设计一个实验证明溴乙烷的Br变成-Br,根据已有的高一的元素化合物知识，学生很容易找出这几个方案:第一个 -方案是取少量溶液与新制氯水反应，有红棕色液体产生，证明原来有Br。第二 -个方案加入AgNO溶液，有淡黄色沉淀AgBr产生，可以证明溶液中有Br。接下3 来利用实验探究来验证 设计方案 关于薪酬设计方案通用技术作品设计方案停车场设计方案多媒体教室设计方案农贸市场设计方案 ，学生就会发现第一个方案可以看到预期现象，但是氯水要求新制取，不太方便。第二个方案没有预想中的淡黄色沉淀，这样就激发学生的好奇心。教师适时抛出?为什么看不到现象,引导学生通过分析实验 -步骤，得出溶液中有NaOH，能与AgNO反应得到AgO暗褐色沉淀，对Br的检验32 产生干扰。此时再问学生?如何修改方案,通过上面的分析后，结果自然水到渠 -".asting base nearby, as one aspect of the development of the national guerrillaoccupied areas and along the coastal areas, should be well organized guerrilla and in rivers, lakes and estuaries and build l-ke of hongze Lake area branching stream of all enemy he Lay base in the area. In May 1938, Chairman Mao Zedong in the guerrilla war in the strategic issues of: "North zone, South of tare also some merchants to Yan Tao DUN Cun opened shop. Cang during the depression as a regional political center and militar theretownships, at this time of grave, there has been a monstrous prosperity, Nanxun town, even the neighboring Zhejiang Province,nvenience. Therefore, this has become the refuge of many, where Wujiang gentleman most of the refuge is not the fall of four cross, easy hidden combat, and no Highway, traffic inco-e, is located in remote, territory size Lake swing dotted, river port crissing) seven County (wuxing, and return Ann, and Tongxiang, and jiaxing, and show water, and Wujiang, and earthquake Ze) of makd jiaxgxiang County, and Wuxing County adjacent, ancient for two province (River, and Zhejiang) three House (Suzhou, and huzhou, anwn of Nan Ma Street, and Tan Qiu street of rotten Brook Tang West of area, in Wujiang South border, and Zhejiang Province Tonwar, strict tomb for seventh district, its regional range for this Taoyuan town and to-ng relocated to the countryside village. Prettee, with espionage, sabotage, standing and political team. Soon, the tomb of the Wujiang District Committee of the Kuomintaion and Finance Commilujianhua (South area ahead Office Director and to war victory)]. County Government operates 3 Civil Affairs, finance, educat 5 - 成，学生很快领悟到除去NaOH的干扰就要加入过量的HNO中和。然后提出?如3 何鉴别卤代烃中具有卤素原子,由于前面四步具有梯度的问题已经被学生解决 了，只要将上述实验步骤归纳就能得到普遍性的规律。这种探究学习方式降低了 学生学习难度，并由于问题的逐步解决，提高了学生解决问题的信心。而且有别 于传统的课堂，学生表现的非常积极，课堂气氛非常活跃，取得了比较好的效果。 在实验探究中培养了学生善于思考，善于利用已有条件解决问题的能力。 lujianhua (South area ahead Office Director and to war victory)]. County Government operates 3 Civil Affairs, finance, education and Finance Committee, with espionage, sabotage, standing and political team. Soon, the tomb of the Wujiang District Committee of the Kuomintang relocated to the countryside village. Pre-war, strict tomb for seventh district, its regional range for this Taoyuan town and town of Nan Ma Street, and Tan Qiu street of rotten Brook Tang West of area, in Wujiang South border, and Zhejiang Province Tongxiang County, and Wuxing County adjacent, ancient for two province (River, and Zhejiang) three House (Suzhou, and huzhou, and jiaxing) seven County (wuxing, and return Ann, and Tongxiang, and jiaxing, and show water, and Wujiang, and earthquake Ze) of make, is located in remote, territory size Lake swing dotted, river port criss-cross, easy hidden combat, and no Highway, traffic inconvenience. Therefore, this has become the refuge of many, where Wujiang gentleman most of the refuge is not the fall of four townships, at this time of grave, there has been a monstrous prosperity, Nanxun town, even the neighboring Zhejiang Province, there are also some merchants to Yan Tao DUN Cun opened shop. Cang during the depression as a regional political center and military base in the area. In May 1938, Chairman Mao Zedong in the guerrilla war in the strategic issues of: "North zone, South of the Lake of hongze Lake area branching stream of all enemy-occupied areas and along the coastal areas, should be well organized guerrilla and in rivers, lakes and estuaries and build lasting base nearby, as one aspect of the development of the national guerrilla".