3水結冰了課件科學三年級上冊教科版

水結冰了Thewateriscrying回顧/Review水water水蒸氣steam液態(tài)/liquid看得見/visible摸得著/touchable有固定體積/fixedvolume較重/heavy氣態(tài)/gas看不見/invisible摸不著/untouchable沒有固定體積/nofixedvolume較輕/light無色/colourless無味/tasteless透明/lucency會流動/flow無固定形狀/unfixedshape回顧/Review沸騰boil這是一杯熱水，把它放置一段時間后會發(fā)生什么變化？Thisisacupofhotwater.Whathappenswhenyouleaveitforawhile?探究/Explore如果一直讓水的溫度下降，會出現(xiàn)什么情況？Whathappensifyouletthetemperatureofthewaterdropallthetime?探究/Explore把水放入冰箱冷凍室內(nèi)，一天后水有什么變化？是什么使水發(fā)生了變化？Putthewaterintherefrigerator.Whathappenstothewaterafteraday?Whatmadethewaterchange?探究/Explore探究/Explore觀察/Observe取一些冰塊，仔細觀察?！け鞘裁搭伾?？·隔著冰能不能看到其他物體？·冰塊有固定形狀嗎？·用手觸摸冰塊，有什么感覺？Takesomeicecubesandobservethemcarefully.·Whatcoloristheice?·Canweseeotherobjectsthroughtheice?·Doesicehaveafixedshape?·Howdoyoufeelwhenyoutouchice?實驗/Experiment1.在試管中加入四分之一的清水，在水面出做好標記2.將試管插入到燒杯的碎冰中，測量試管中水的溫度。3.保持溫度計位置不變，等待試管中的水結冰4.測量試管里的水開始結冰時的溫度5.水完全結冰后，在試管上標記冰柱的高度FillatesttubewithaquarterofwaterandmakeamarkonthesurfaceInsertthetubeintothecrushediceinthebeakerandmeasurethetemperatureofthewaterinthetube.HoldthethermometerinthesamepositionandwaitforthewaterinthetesttubetofreezeMeasurethetemperatureatwhichthewaterinthetesttubebeginstofreezeOncethewaterhasfrozencompletely,marktheheightoftheicicleonthetesttube探究/Explore比較冰和水，它們有哪些相同的特征和不同的特征？Comparingiceandwater,whatdotheyhaveincommonandwhatdotheyhaveinother?水water冰ice探究/Explore·水在什么條件下會結冰·水結冰后有哪些變化？·冰還是水嗎？UnderwhatconditionsdoeswaterfreezeWhathappenstowaterwhenitfreezes?Isicewater?總結/Summarize·水在什么條件下會結冰·水結冰后有哪些變化？·冰還是水嗎？UnderwhatconditionsdoeswaterfreezeWhathappenstowaterwhenitfreezes?Isicewater?拓展/Expand我們來看看有關冰的美好瞬間吧Let'stakealookatsomebeautifulicemoments拓展/Expand我們來看看有關冰的美好瞬間吧Let'stakealo