1、 Listening and writing You will hear a conversation in which a teacher helps a student do an experiment.Read the Aim below and predict the Result.Aim:To find out if there is a change in weight when the metal magnesium burns in air.Result:_.Aim:_ _To find out if theres a change in weight when magnesi
2、um burns in air.Listen and complete the description of the scientific experiment.Apparatus:_Method:_ _ _Magnesium,Bunsen burner,a balance,a crucible.First,put the magnesium in the crucible.Then put the crucible on the balance and weigh it.Next,heat the magnesium.Light the Bunsen burner and hole the
3、crucible over it.Finally weigh the magnesium again.Result:_Conclusion:_ _It weighs a little more than before.There is a change in weight when magnesium burns in air.Listening text(Mr C=Mr Chen,Z.K=Zhou Kai,L.K=Li Kang)Mr C:OK,boys and girls,were going to do an experiment.Come a bit closer.The closer
4、 you are,the more youll see!Thats right!Now,whats the aim of this experiment,Zhou Kai?Z.K:We want to find out if theres a change in weight when magnesium burns in air.Mr C:Thats right.So what do we need first?Z.K:Um We need some magnesium.How much do we need?What about this piece?Is this piece OK?Mr
5、 C:No,we need rather more than thatabout two and a half grams.We need a piece which is much bigger than that.Z.K:OK And we need a Bunsen burner a balance and a crucible to put the metal in Here they all are.Where do we go from here?Mr C:Well,first,put the magnesium in the crucible.Then put the cruci
6、ble on the balance and weigh it.Z.K:OKMr C:How much does it weigh?Take a look,everyone.Is it any heavier?Z.K:Um It weighs two and a half grams.Do you want me to write that down?Mr C:Yes,write it down.What next?Z.K:Yes Um,next,were going to heat the magnesium.So I light the Bunsen burner.After that,I
7、 hold the crucible over it Oh look,its burning with a white light!Its getting brighter and brighter!Mr C:Its pretty,isnt it?Keep the noise down,boys and girls,please.Z.K:Um lastly,we need to weigh the magnesium again It weighs four grams now.Mr C:So what does that tell you?Z.K:It weighs a little mor
8、e than before.Mr C:How much more?Z.K:1.5 grams more.Mr C:And what does that mean?Z.K:It means that there is a change in weight when magnesium burns in air.Mr C:Youve got it!Well done!So now,lets do the same experiment with copper.Come along.Li Kang,its your turn now.What do you think will happen if
9、you heat copper?Z.K:I think itll be a lot heavier than magnesium.Shall I begin?Mr C:Yes,go ahead!1.“Where do we go from here?”means _.A.What shall we do next?B.Is this the right way?2.“Keep the noise down”means_.A.Dont talk B.Talk quietlyChoose the correct meaning.3.“Youve got it”means _.A.Youve understood B.You have something 4.“Go ahead!”means _!A.Go away B.Begin 5.“Its your turn”means _.A.Youre next B.Turn round
