1、有两种变化:化学变化和物理变化,那么你知道化学变化和物理变化的区别吗?Chemical Change and Physical ChangeThere are two kinds of changechemical change and physical change.In a chemical change, there is always a new substance formed.Breaking up water into hydrogen and oxygen is a chemical change.In each of the chemical change at least
2、one new substance is formed.A change is not a chemical change if it doesnt form a new substance.Physical changes are very common, too.There are many examples.You can make a physical change by tearing a piece of paper into two, or by cutting a piece of iron with a lathe.Here the paper is still paper,
3、 and the iron is still iron.Another way of making physical change is dissolving something in water.When you dissolve salt in water, the salt disappears.You may think that a new substance has been formed.But in fact there is no new substance.The salt is still salt.You can still taste it.So the dissol
4、ving of anything is a physical change.When water freezes, the change is also a physical one.The water changes from liquid to solid.But it is still the same substance.That is why the freezing of anything is a physical change.And people often tell the differences between a chemical change and a physic
5、al change through some experiments.We should try to explore the magical science world by doing experiments by ourselves.阅读障碍词1hydrogen n氢气2tear v撕扯3lathe n车床4freeze v结冰;冷冻5magical adj.魔力的诱思导读根据短文内容,判断正误(T/F)1In a chemical change, there is always a new substance formed.(T)2Breaking up water into hydr
6、ogen and oxygen is a physical change.(F)3Water changing from liquid to solid is a chemical change.(F) .匹配下列单词的词性及汉语意思()1.expandAn.电()2.mixtureBn.结论()3.electricityCn.混合物()4.conclusionDn.目标;目的()5.aimEn.设备;装备()6.reactFvi.形成 ()7.equipmentGvi.漂浮()8.ordinaryHvi.(化学)反应()9.float Ivi.膨胀()10.formJadj.普通的;平常的答
7、案15ICABD610HEJGF.选择下列句中词组的汉语意思A想出;考虑B将按顺序排列C弄清楚,查明D在底端E往加入F把关在外面1Do you want to add your name to the list?_2She likes to put everything in order in daily life._3Close the door and keep the cold air out of the room._4Can you think of any other way to work out the problem?_5The answer is at the bottom
8、 of the page.Have you found it?_6The teacher was very angry when he found out that the student had been lying._答案16EBFADCPassage AIt is hard to think of a world without metals. Different metals have different uses, for example, steel is used in cars, and iron is used in electrical equipment.When we
9、use metals, it is important to know how they react with different substances, for example, water and oxygen.The reaction of metals with these substances can be put in order.Here is a table with the metals that react most at the top, and the metals that react least at the bottom.A篇很难想象一个没有金属的世界。不同的金属
10、有不同的用途,比如,钢用来造车,铁用来造电力设备。使用金属时,要了解金属和不同的物质(例如水和氧)如何发生反应,这一点很重要。(不同的)金属与这些物质的反应程度可以按顺序排列起来。下面表格中的金属反应最强烈的排在上面,反应最弱的排在下面。助读讲解It is hard to .中it是形式主语,真正的主语是to think of .。When we use metals是when引导的时间状语从句,主句是it is important to.,其中it是形式主语,动词不定式to know .是真正的主语,而how they react with different substances是宾语从句
11、,作know的宾语。that react most at the top是that引导的定语从句,修饰先行词metals。MetalHeated in oxygenReaction with water or steamPotassiumBurns to form an oxideReacting with cold waterSodiumCalciumMagnesiumReacting withsteamAluminiumZincIronReacts slowlyPartial reactionCopperPartial reactionNo reactionPassage B A Simp
12、le Scientific ExperimentBelow is a description of a simple scientific experiment. It shows us how iron reacts with air and with water.,金属在有氧状态下加热与水或水蒸气的反应钾燃烧后生成氧化物与冷水反应钠钙镁与水蒸气反应铝锌铁反应缓慢部分反应铜部分反应不反应B篇一个简单的科学实验下面是对一个简单科学实验的描述。这篇文章向我们表明,铁是怎样与空气和水反应的。助读讲解Below is a description .是完全倒装句,主语是a description,be
13、low is是系表结构。show后跟双宾语,us为间接宾语,直接宾语是how引导的宾语从句。Aim:To find out if iron rusts(生锈) (a) in dry air; (b) in water that has no air in it (airfree water); (c) in ordinary water.Apparatus:3 clean iron nails; test tubes; test tube holder; cotton wool; oil; Bunsen burner.目的:发现铁是否在下列状态下生锈:(a)在干燥的空气中;(b)在没有空气的水
14、中(无空气水);(c)在普通的水中。仪器:三颗洁净的铁钉、试管、试管夹、棉花、油、本生灯(即煤气灯)。助读讲解To find out if iron rusts是目的状语,其中if意为“是否”,引导宾语从句。that has no air in it是that引导的定语从句,修饰先行词water。Iron in dry airMethod(1)Put some iron nails at the bottom of a test tube.(2)Push some cotton wool down the tube.(3)Leave the tube for one week.ResultAf
15、ter one week, the nails have not rusted.ConclusionIron does not rust in dry air.Iron in airfree waterMethod(1)Halffill a test tube with water.(2)Boil(煮沸) the water for three minutes.(This makes sure there is no air in the water.)(3)Put two or three clean nails in the water.(4)Add some oil to the wat
16、er.This will keep air out of the water.(5)Leave the tube for one week.铁在干燥的空气中方法(1)把若干铁钉置于试管底部;(2)顺着试管塞入一些棉花;(3)把试管放置一周。结果一周后,铁钉未生锈。结论铁在干燥的空气中不生锈。铁在不含空气的水中方法(1)在试管中加一半水;(2)将水烧开保持3分钟(这样做可以保证水中无空气。);(3)在水中放23颗洁净的铁钉;(4)在水中加些油,这样做可防止空气进入水;(5)把试管放置一周。助读讲解there is no air in the water是省略了引导词that的宾语从句。Resul
17、tThe nails do not rust in the tube with airfree water.ConclusionIron does not rust in airfree water.Iron in ordinary waterMethod(l)Halffill a test tube with water and add two or three clean nails.(2)Leave the tube for one week.ResultThe nails rust in the tube with ordinary water.ConclusionIron rusts
18、 in ordinary water.结果铁在没有空气的水中未生锈。结论铁在没有空气的水中不生锈。铁在普通的水中方法(1)在试管中加一半水,并在水中放23颗洁净的铁钉;(2)把试管放置一周。结果铁钉在装有普通水的试管中生锈。结论铁在普通的水中会生锈。第一步速读了解文章主题和段落大意速读P4445教材课文,回答下列问题1Read Passage A and choose the best title for it.AThe Different Uses of MetalsBThe Reaction of MetalsCThe Reaction of Metals with OxygenDThe
19、Reaction of Metals with Water答案B2Read the subtitles in Passage B and answer what should be included in a description of an experiment.(1)Aim(2)Apparatus(3)Method(4)Result(5)Conclusion第二步细读把握文章关键信息细读P4445教材课文,选择最佳答案1The table in the passage is arranged in order of _.Ametal kindsBreaction activitiesCv
20、alues of metalDthe first letters of the words2According to the table, which metal is most suitable to make our daily kitchenware(厨房)?AZinc.BIron.CCopper.DMagnesium.3The experiment in Passage B shows us _Ahow iron rusts with waterBiron is quite easy to rustChow to prevent iron from rustingDhow iron r
21、eacts with air and with water4The purpose of these three experiments in Passage B is _Ato find out how iron reacts with water and with airBto find out how important iron isCto find out how to do the experiment of irons reaction with water and with airDto find out how to keep iron rustless答案14BCDD第三步
22、研读能力升华接轨高考根据P4445教材课文,在空白处填入1个适当的单词或括号内单词的正确形式Different metals have different uses.When we use metals,it is important 1.to know(know) how they react with 2.different(differ) substances.By doing some simple experiments,we can achieve the 3.following (follow) aims.Firstly,put them 4.in order according
23、 to the reaction.Secondly,find out if iron rusts in dry air,in airfree water and in ordinary water.In order to achieve the second aim,we need different pieces of 5.equipment(equip).6.Having made(make) full preparations,we can go to the different stages of the experiment.During each stage,relative methods should 7.be used(use)After that,we 8.will get(get) different results and make the conclusions 9.that iron does not rust in dry air and in airfree water 10.but it rusts in ordinary water.