一节“金属”双语课，本文主要内容关键词为：双语论文,金属论文，此文献不代表本站观点，内容供学术参考，文章仅供参考阅读下载。
上海市的二期课改已经进入了第4个年头，对化学学科知识的要求有一定降低，但更加注重学生的综合能力的提高。本节双语课的内容涉及金属的性质和用途，让学生体会“结构决定性质，性质决定用途”这句话的含义。学习内容与学习生活非常接近，知识性不是特别高深，可发挥上海学生英语水平较高的优势，提高学习兴趣，促进英语和化学的学习。
【开始上课】Class begins.Hello everyone! Sit down,please.
【介绍本节课的主要内容，使学生知道学习目标】
Today we'll learn something about metals.
First,the use of metals.
Second,the physical properties of metals.
Third,the structure of metals.
Then,we'll learn to use the structure of metals to explain their physical properties.
Last but not least,we'll have a discussion on how to use the limited resources of metal ores.
Do you understand?
【引入】Now shall we start?
Most of the elements in the earth are metals.Nowadays,about 60 metals are in use.They are very important in our daily life.Many things are made of metals.
Can you show me some examples?
【小组讨论金属的用途】Pair work.Find out what kind of metals is used in our daily life.
……【学生回答】
Well done.Any more volunteers? Who would like to have a try?
……【学生补充】
According to what you've just told me,lots of things such as cars,pots,knives and forks,food cans are all made of metals.In fact,we cannot live without them.
Do you agree with me?【边讲边放金属使用的图片】
【进入第2部分】Here comes our second part.
Since metals are so important in everyday life,do you know their physical properties?
Metals have properties that made them different from other materials,such as wood,glass or plastic.We all know that the use of a metal depends on its properties.
For example,iron is strong than sodium; gold has higher anticorrosive ability than aluminium.
I think you've learned some in junior high school.Do you still remember them? I'd like you to have a discussion.And then tell me something about physical properties of metals.Group work,please.
……【学生回答】
Good job!【教师鼓励】
【作为学生已有知识，讨论后直接总结金属的物理性质】
In conclusion:
1.Metals are solid at room temperature.
2.Metals are shiny.
3.Metals are good conductors of electricity and heat.
4.Metals are ductile and malleable.
Now are you clearer about the physical,properties of metals?【询问，了解学生的接受情况】
【开始第3部分】
Now let's take up the next one,the structure of metals.
The properties of a metal depend on its structure.
Understand?
Ok.Let's look at the picture.
The figure shows how the atoms are arranged in typical metal.In metals,the atoms are arranged in a regular pattern to form a giant lattice structure.
【举例分析】Consider the atoms in sodium as an example.A sodium atom has the electron arrangement 2,8,1.The outer-shell electron is quite a long way from the positive sodium ion.In a piece of sodium,these outer shell electrons are free to move.The moving electrons are often called free electrons and often described as a "sea" of electrons.
What holds the atoms together in a metal? Please think it over...
Each positive ion is attracted to the "sea" of elec trans.The attraction holds the metal atoms together.This type of bonding is found only in metals and is called metallic bonding.【提出金属键的概念】
Can you catch me?【关于金属键的内容是难点，可用汉语解释一遍】
Now please have the group work.
Try to explain the physical properties of metals with the knowledge of the structure of metals.
After the discussion,each group is expected to tell me something about it.Anything will do.【讨论之后，用金属的微观结构解释金属的性质】
……【学生回答】
【为帮助学生理解，让部分学生用中文回答】 Are you ready? That's ok.If you can't say it in English you can in Chinese.
......Something like that.
Terrific! I'm impressed.You are all clever.
Ok,Let's watch a flash......【观看Flash，加深理解】
导电性：Metals conduct electricity by the movement of the electrons.When a current flows,electrons move into one end of the metal and the same number of electrons leave the other end.
导热性：When one end of a metal is heated,the electrons get more energy.They move faster and hit other electrons move often.Slowly,energy moves along the metal.
延展性：The atoms in a metal are arranged in layers.When a force is applied,the layers can slip over each other.The metal does not break as the "sea" of electrons hold it together.
固体，高熔点：To separate all the atoms in a metal needs a lot of energy,because their bonding is strong.Therefore,their melting points are high.And,for this,metals are usually solid at normal temperature.
Am I made myself understood? Shall I say it in Chinese again?【多次注意学生的反馈】
【第4部分，资源保护】Now,the last part:the recourse of metal ores.
Each year,the population of the world is increasing and people use more and more metals.The metal compounds in the earth will not last forever.Some day in the future,they will be used up!
Can you imagine what will happen then?
What should we do now to avoid it?
...Yes,We should conserve our resources.
But,how to conserve our resources? Please have a discussion.
Let's sum up.
...Good point./Well done./Good job.【学生回答，教师鼓励】
Before the metals on earth are used up,we must learn to use metals wisely.①To use less metals.②To use other materials instead of metals.③To recycle used metals.
Am I understood?
Recycling is a very good point.
Do you know anything else about recycling?
What is recycling?...
Can you give me some more examples?...
Group work.Have you recycled any metals in your daily life?
Let's come to a conclusion,shall we?...
Class is over.Goodbye everyone.
本节课的教学目标是让学生掌握金属的物理性质和化学性质；以金属钠为例，理解并学习用金属的结构对其性质加以解释，这也是本节课的难点所在；真切体会“结构决定性质，性质决定用途”的含义；以铝为例，对金属的循环使用过程有一定了解。通过本节课的学习要培养学生的推理能力和理论联系实际的能力。还要激发学生环保意识和对科学的热爱。双语教学要看学生的接受情况，必要的时候用汉语补充讲解。
标签：双语论文;