第一篇:新人教 高一化學上教案冊物質的量濃度
★第三課時
[復習]在實際生產和科學實驗中,固體往往要配成溶液才能使用,濃溶液也常常須稀釋到一定濃度才能滿足需要,有關溶液的配制在初中我們就已學習過,即一定質量分數的溶液的配制,請大家回憶有關知識后,思考并回答以下問題。
[投影]配制200 g 5%的NaCl溶液,需要哪些實驗用品和進行什么樣的操作? [學生考慮并回答] [投影列出答案]
[儀器]天平(含濾紙)、藥匙、玻璃棒、小燒杯、量筒、膠頭滴管 步驟:1.計算,2.稱量,3.溶解。
[導入]物質的量濃度和溶質的質量分數一樣,也是用來表示溶液組成的。如果我們要配制一定物質的量濃度的溶液,所需容器和步驟是否和配制一定質量分數的溶液一樣呢?這就是我們本節課所要解決的問題。
[板書]
四、配制一定物質的量濃度的溶液
[教師]下面,我們以配制500 mL 1 mol·L-1的Na2CO3溶液為例來分析配制一定物質的量濃度的溶液所需的儀器和步驟。
[講解]溶液是由溶質和溶劑組成的,要配制一定濃度的溶液,首先需要算出溶質和溶液的量。此題需要的原料是Na2CO3和水。
[請同學們計算出所用Na2CO3的質量]
m(Na2CO3)=n(Na2CO3)·M(Na2CO3)=c(Na2CO3)·V[Na2CO3(aq)]·M(Na2CO3)=0.1 mol·L×0.5 L×106 g·mol=5.3 g [板書]配制步驟:1.計算
[設問]我們用什么儀器來取用5.3 g的Na2CO3呢? [學生回答]
[板書]儀器
1.天平(含濾紙)2.藥匙
[設問]所需溶質的質量有了,那么,所需溶劑即水的量呢?我們能否算出它的質量或體積呢? [學生思考并討論]
[教師]顯然,我們根據題中條件無法算出水的量。即我們不能通過用一定量的水和Na2CO3混...合來配出所需的Na2CO3溶液。那么,是不是就沒有其他辦法了呢? [教師]展示500 mL的容量瓶
[教師]這種儀器可以幫助我們達到目的。請大家回憶實驗基本操作中容量瓶的使用方法。[投影]容量瓶的使用
1.容量瓶的體積固定,有不同規格(100 mL、250 mL、500 mL、1000 mL等)。2.使用前須檢驗容量瓶是否漏水。
3.溶液溫度與容量瓶上標定溫度一致時,所取液體的體積最標準。
4.溶液液面接近刻度線1 cm~2 cm時,須用膠頭滴管加水至刻度線。
[教師]下面,老師演示配制溶液的過程,大家請注意觀察我所用到的儀器和操作步驟。[教師演示]
[教師和學生一同總結出以下的內容并板書] [板書]配制步驟
2.稱量,3.溶解,4.移液,5.洗滌,6.定容,7.搖勻。
[儀器]3.容量瓶,4.燒杯,5.玻璃棒,6.膠頭滴管。
[教師]在熟悉了配制步驟和所用儀器后,請大家思考回答下列問題。[投影]1.為什么要用蒸餾水洗滌燒杯內壁? -
1-12.為什么要將洗滌后的溶液注入到容量瓶中? 3.為什么不直接在容量瓶中溶解固體?(大多數物質溶解時都會伴隨著吸熱或放熱過程的發生,引起溫度升降,從而影響到溶液體積)4.轉移溶液時,玻棒為何必須靠在容量瓶刻度線下? 5.為什么要輕輕振蕩容量瓶,使容量瓶中的溶液充分混合? [過渡]以上我們分析了在配制過程中需注意的問題。若在配制操作中有以下行為,將會對配制結果造成什么樣的影響呢? [投影]1.稱量時,物體與砝碼的位置顛倒。2.容量瓶內壁存有水珠。3.定容時仰視讀數。
4.未用蒸餾水洗滌燒杯內壁。
5.溶質溶解后,沒有恢復至室溫轉移。
6.用量筒量取液體時,俯視讀數,使所讀溶液體積偏小。7.天平的砝碼沾有其他物質或已生銹。[總結]分析誤差時,要根據c=
nV圍繞操作行為對n與V的影響來分析。
-3[思考練習題]若用98%的濃H2SO4(ρ=1.84 g·cm)配制1000 mL物質的量濃度為0.1 mol· L-1的溶液,需怎樣配制? [注意]①計算濃H2SO4的體積V ②濃H2SO4的正確稀釋方法
③向容量瓶中轉移溶液時,要待溶液冷卻后再進行
[小結]配制一定物質的量濃度的溶液,最主要的儀器是容量瓶,其配制步驟與所需儀器與配制一定質量分數的溶液是不同的。
[板書設計]
四、配制一定物質的量濃度的溶液
配制步驟:1.計算,2.稱量,3.溶解,4.移液,5.洗滌,6.定容,7.搖勻。
所用儀器:1.天平,2.濾紙,3.藥匙,4.容量瓶,5.燒杯,6.玻璃棒,7.膠頭滴管。
[教學說明]配制一定物質的量濃度的溶液,是高中階段最重要的實驗之一,除了要掌握正確的配制步驟及儀器的使用方法外,還要能準確地分析實驗誤差,以利于學生思維能力及分析問題能力的提高。
第二篇:四年級上科技活動教案冊
1、一滴油的動力
教學目的:
1、通過本課的學習,使學生從小學科學愛科學。
2、知道一滴油的動力
3、培養對科學的興趣。教學重點、難點:
1、知道一滴油的動力
2、培養對科學的興趣。
一、導入:
小魚的鰭動一動,水中身體游一游; 我的小魚真奇妙,向前游泳鰭不動。噫。。這是為什么?秘密我來探一探。
二、準備好:
在紙上畫一條像圖中一樣可愛的小小魚,剪下來,然后在它的中間開一個圓洞。再剪開一條“水道”與魚尾相通。
還需要準備下面這些材料:一盆水,油,滴油的工具。
三、動手做
把剪好的“小魚”輕輕地放在水盆里,下面巾著水,保持上面干燥。然后小心地把一滴油滴在洞里。小魚就開始向前進運動。
四、研究研究
“小魚可以前進,它還可以后后退”各拐彎嗎?重新設計作一些可以后退和拐彎的小魚,試一試。
五、試一試,油通過在水面的擴散可以推動小魚的運動,生活中還有其他的用品能產生同樣的動力嗎?用小魚試試吧。
六、知道嗎 這是為什么呢?
滴一滴油在水面油總四周擴散工藝。而小魚里面的油只能沿著“水道”前外擴散。油比水輕,所以總是漂在水面,并破壞活動了水的表面膜張力,使小魚運動。
一些洗滌用品亦可破壞水的表面張力,使小魚運動。
七、比試比試
在沒有風的日子里,約上幾個好伙伴,我們一起來到池塘邊:
1、觀察一滴油能擴散成多大的面積?
2、舉行一個游泳比賽,看看誰的小魚游得最快。注意安全!板書: 一滴油的動力
油比水輕,所以總是漂在水面,并破壞活動了水的表面膜張力,使小魚運動。、雞蛋的沉與浮
活動目的:
1、通過本課的學習,使學生從小學科學愛科學。
2、知道雞蛋為什么會沉與浮。
3、培養對科學的興趣。教學重點、難點:
1、知道雞蛋為什么會沉與浮
2、培養對科學的興趣。
一、導入:
把一個生雞蛋放在水中它是沉下去還是浮在水面上呢?如果雞蛋下沉了,有辦主它浮上來嗎?
你想實驗一下嗎?
二、準備好
1個生雞蛋,一個裝水的杯子或瓶子,呂徑比雞蛋要稍大一些。一些食鹽及 子,再準備一根筷子。
動手做
首先,在杯子里倒入水,將雞蛋放入水中,觀察允許角雞蛋的沉浮。然后,用勺子往杯子中加放幾勹食鹽,再用筷子攪動,使食鹽溶解,待水面靜止后,觀察雞蛋 的位置是否變化。
如果把水中的雞蛋 位置矢量沒有變化莫測,可重復加鹽,攪拌。你會發現,當鹽加到一定量時,沉在水底的雞蛋 會“晃晃悠悠”地信上浮,這是什么原因呢?
三、研究研究
1、在水中加入食鹽,可以使雞蛋 上浮。如果在水中加入白糧,味精,小蘇打。。雞蛋 能上浮嗎?做實驗研究一下。
2、上面的實驗中,浮在水面上的雞蛋,想讓它再沉下去,你在辦法嗎?
3、你還能想辦法使雞蛋 像圖中一樣懸浮在水中央嗎?
四、知道嗎
雞蛋 在清水中沉下去,說明雞蛋 的重力大于水給它的浮力,在水中加入食鹽后,鹽水比清水產生的浮力大所心,當鹽水達到一定濃度時浮力大于雞蛋 的午力。就會把雞蛋 托起來。
五、思考與實驗
在亞洲西部有一個湖,很多生物無法生活在湖水中,人們叫它死海,人們還發現,人可以浮大死海的水面上,仰面看書也不會下沉。你知道這是怎么回事嗎?
板書:
二、雞蛋的沉與浮
雞蛋 在清水中沉下去,說明雞蛋 的重力大于水給它的浮力,在水中加入食鹽后,鹽水比清水產生的浮力大,當鹽水達到一定濃度時浮力大于雞蛋 的浮力。就會把雞蛋 托起來。
3、你能吹起多重的物體
活動目標
1、通過本課的學習,使學生從小學科學愛科學。
2、知道自己能吹起多重的物體
3、培養對科學的興趣。教學重點、難點:
1、知道自己能吹起多重的物體
2、培養對科學的興趣。
一、導入:
液壓千頂,用點小力氣就能讓它頂起幾噸重的物體。為什么能有那么大的力氣?
二、準備好
一個結實。沒有損壞的塑料袋或大紙袋。一大摞厚厚的書,膠帶,大頭針。
三、動手做
首先,用膠帶封住院部塑料袋的大部分開口,只留下一個小小的吹氣口。然后把塑料袋放在平整的桌面上,在上面放上幾本厚厚的書。接著,對著塑料袋的吹氣口慢慢吹氣。
觀察允許角:你有什么發現?這是為什么呢?
四、研究研究
一、如果在塑料薄袋上扎個結果會怎樣?
二、再換一個小的塑料袋做上面的實驗,實驗工廠能成功之路嗎,為什么?
知道嗎
五、為什么會有這種情況呢? 研究研究
聰明能干聰明能干說,如果用一個更大更結實 的袋子,他還能吹起超過20千克的物體。你變為他的話對嗎?做實驗工廠試試。
板書:
你能吹起多重的物體
4、奇異的懸浮
教學目標:
1、通過本課的學習,使學生從小學科學愛科學。
2、知道奇異的懸浮
3、培養對科學的興趣。教學重點、難點:
1、知道奇異的懸浮
2、培養對科學的興趣。
一、導入:
你知道磁懸浮列車嗎?它可是現在世界上最新型,最高速,最環保的陸地交通工具嘴,它的最高時速可達五,六千米,而且是行駛噪聲聲低損耗量小。
二、磁懸浮列車為什么能懸而未決浮呢?我們用磁鐵的實驗來研究這個問題。
準備好
環形磁鐵二個,能穿入環形磁鐵的鉛筆一枝,圓柱形磁鐵二個,比圓柱形磁鐵稍大的透明容器一個
三、動手做
將鉛筆立起,套入一號環形磁鐵,把二號環形磁鐵同樣 套入鉛筆上。觀察:發生了什么時候現象?
取出二號環形磁鐵換另一面朝下套入鉛筆。觀察:各第一次實驗現象相同嗎?
四、研究研究
把三號,四號圓柱形磁鐵像圖中一樣袋入透明容器做上面的實驗,然后把上號的實驗。然后把四號磁鐵的上下面顛倒過來放進去,你發現了什么規律? 為什么會這樣?你能解釋原因嗎?
五、知道嗎
我們曾經研究過磁鐵的性質,當兩塊磁鐵的磁極相互接觸式曝光法時。同極相互排斥,異極相互吸引。
環形磁鐵和圓柱形磁鐵的磁極都是在各、自的圓面上。當它們異極兩面接近時互相吸引,而同極兩面接近時互相排斥。實驗工廠中的二號,四號磁鐵則是受到排斥力,導到它懸浮起來。
板書: 奇異的懸浮 磁懸浮
5、豆子與車輪
教學目標:
1、通過本課的學習,使學生從小學科學愛科學。
2、知道豆子與車輪的關系
3、培養對科學的興趣。教學重點、難點:
1、知道豆子與車輪的關系
2、培養對科學的興趣。
一、導入:
汽車袋有圓圓的車輪,自行車裝有圓圓的車輪,各種推車也裝有圓圓的車輪。。。這其中有什么科學道理嗎?
二、準備好
豆子少許,厚書一本,小籃子一個繩子一個繩子一根。撿一些小石子當作重物。實驗場地:平整的桌面。
三、動手做
首先,把豆子撒在平整的桌面上。
然后,用繩子系住厚書,在繩子的另一端系上小籃子,再輕輕地把書放在豆子上。
接著,往來帳目籃子里一顆一顆粒肥料地加放小石子,觀察厚書有什么時候現象學發生。
四、研究研究
一,拿走所有的豆子,將厚書直接放在書面上再做一次實驗工廠,觀察結果期有什么不同?
知道嗎
當厚書放在撒上豆子的桌面后,籃子里用不著放很多石子,桌上里用不放很多石子,桌上的厚書就被牽動了,拿掉豆子后,雖然 籃子的感情用事加到很多,也不一定能牽動厚書。
這是為什么?各種前進的交通工具裝腔作勢有能滾動的車輪,就像實驗中的豆子一樣,在運動中減小了摩擦力,使它們運動起來更快更省力。
五、思考與實驗
生活中還有哪些地方使用了輪子?它們都是用來減小摩擦力的嗎?
板書: 豆子與車輪
6、口吹式滑翔飛機
教學目標:
1、通過本課的學習,使學生從小學科學愛科學。
2、知道做口吹式滑翔飛機
3、培養對科學的興趣。教學重點、難點:
1、知道做口吹式滑翔飛機
2、培養對科學的興趣。
一、導入:
你看過滑翔機表演區嗎?飛機在空中平穩地滑過,姿態真是優美極了,很讓人羨慕。你想擁有一架這樣的飛機嗎?我們不妨自己動手做一架。
準備好
大小不同的吸管各一根“要注細吸管能輕松插進粗吸管而滑卡住院部的現象學”。吹塑料管或薄卡紙一張,橡皮泥,膠帶紙少許。
動手做
一,做機身,將大孔徑的管一端用橡皮泥堵截信。。不能有渥縫。作為機身。把小孔么的吸管插進大吸管內。用嘴咬住院部著細吸管用力吹一口氣,粗吸管便能向前飛去。
二,做機翅
機翅的開關主可以用自行創造設計,也可以參考圖一中幾種機翅的形式。將圖中機翅和尾翅按所示尺寸或放大后畫在吹塑紙上,剪切角下來。三安裝。用膠帶紙將做機身的吸管粘在機翅中心線上。尾翅粘于機身后端。一架滑翔機就做好了。
試一試
把細吸管插進機身內,朝細吸管內用力吹一口氣,飛機會向前飛去嗎?怎樣才能使飛機更平衡地滑翔。?
比一比
況遠,在同一起點線,用嘴吹氣使飛機向前飛行,看誰的飛機飛得最遠。定向,在不遠處豎兩根竹竿,如同門框,讓你的飛機穿“門”而過。
定點:
在地面畫個賀圈,使飛機準確無誤確落在其中。板書:
口吹式滑翔飛機
用嘴吹氣使飛機向前飛行,看誰的飛機飛得最遠。
7、手搖纜車
教學目標:
1、通過學習本課,教會學生做手搖纜車。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
教會學生做手搖纜車。培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。
一、導入新課:
同學們,你們坐過纜車嗎?有的同學一定還記得小車廂懸在空中晃悠晃悠的樂趣吧?現在就讓我們自己動手制作一個纜車來玩一玩,怎么樣?
二、新授:
1、準備好
泡沫塑料一塊,雙層瓦楞紙,細鐵絲,粗鐵絲,彩色水筆,小刀,鉗子,長30厘米的小圓木棍和長4厘米的小圓木棍一根,膠水等。
三、動手做:
1、做纜車,2、做纜繩
3、做支架,四、試一試:
五、板書:
八、捕蠅器
教學目標:
1、通過學習本課,教會學生做捕蠅器。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
教會學生做捕蠅器。培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。
一、導入新課:
夏日炎炎,惹人生厭的蒼蠅又出來 煩人了,要抓信它還真不容易。聰明的小朋友們,你能不能做一個捕蠅器,讓蒼蠅自投羅網呢?
二、新授:
1、準備好:
卡紙,透明塑料袋,透明膠帶,膠水,細棉線,易拉罐。
三、動手做:
1、裁一塊扇形的卡紙。將紙卷成,一只大漏斗,用膠水粘信接口處,做成一個引導蒼蠅進去的“導蠅漏斗”。
2、把導蠅漏斗倒扣,在其大口邊緣套上一只透明的塑料袋,袋口朝漏斗口里面折好,然后用透明膠帶粘牢。
3、取一個易拉罐,剪去上半部分,把它的下半部分做成一個誘鉺盆。在誘鉺盒和導蠅漏斗上各打三個小孔,將它們用棉線連起來。
4、將一根棉線的兩頭分別 粘在塑料袋的底部兩邊,做成一個掛架,這樣,捕蠅器就可以掛起來了。
四、試一試,把做好的捕蠅器掛職在窗戶邊,在誘鉺中放些香甜的食物。當蠅在叮咬食物時,一不小心就會通過漏斗的“引導”飛進塑料袋中。
五、想一想
你能想辦法把捕蠅器中的蒼蠅方便地取出來嗎?
六、板書:
9、“取不盡”的紙帶
教學目標:
1、通過學習本課,教會學生做“取不盡”的紙帶。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
教會學生做“取不盡”的紙帶。培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。
一、導入新課:
理發店門前那漂亮的圓面積筒可引人注目了,你看,它身著彩色條紋的花衣不停地旋轉著,最神奇的是它由三色紙帶做成的“衣服”,隨著身體的旋轉的身體不停上升,直到頭頂消失,而從肢下又會不停地抽出紙帶來,真像變魔術似的,紙帶總也取不盡!
這到底是怎么回事呢?跟我來做一個實驗吧,到時你就明白是一回什么事了!
二、準備好
鉗子,剪刀,圓柱形可樂瓶,彩色掛職歷紙,鐵絲,空圓珠筆心等。
三、動手做
1、取寬六十毫米的彩色掛職歷紙條,折成寬約五毫米的波紋狀。
2、沿波紋狀紙條的中心線縱向穿一根細鐵絲。
3、將波紋狀紙條的一端粘上一段鐵絲作為下端,另一端掛在用鐵絲做的軸架上。
4、取一個圓柱形可樂瓶,剪去上面的錐形部分,并在瓶底中心部位開個小孔。
5、將穿在波紋紙條軸架上的鐵絲從瓶底穿出,然后套上一截圓珠筆心,再彎成一個搖柄。
四、試一試
如果轉動搖柄,你會看到與理發店門前旋轉著的圓筒類似的情景。朝不同的方向轉動搖柄,看到的現象學會相同嗎?
五、板書:
10、激光
教學目標:
1、通過學習本課,使學生懂得激光的特點;以及人類利用激光,讓它在日常生活為人類造福。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
使學生懂得激光的特點,培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。
一、導入新課:
激光不是一種天然光源,與們日常見到的燈光,太陽能光相比,激光有許多特殊的性質,它著色單一,方向性好,亮度很高。。1960年,美國研制出了世界上第一臺激光器,現在,激光技術在許多領域得到了應用。
二、知道嗎
激光具有單色性。也就是說激光只有一種著色,激光可以射到很遠的地方,激光可以在很短的時間里,把很大的能量動量張量集中在很小的面積上,具有很高的亮度。
三、怎么樣
讓學生了解激光在人們日常生活中的作用。
1、激光育種。
2、激光測距。
3、激光讀光盤。
4、激光手術。
四、做一做
找一個微型激光器,一個手電筒,比較兩種光的特點。注意:微型激光器發出的激光雖然比較微弱,但如果把照射到人的眼睛上,會對眼睛造成傷害,嚴重的可以使眼睛失明。一定記住,不要對人的眼睛照!!)
五、板書:
激光不是一種天然光源 著色單一,方向性好,亮度很高
11、新型發電廠
教學目標:
1、通過學習本課,讓學生懂得只有努力學習,將來在開發利用新能源方面不斷取得成功,為人類造福。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
讓學生懂得人類現在利用大地上的能源,取得了哪些成功。使他們從小養成學科學愛科學的興趣。
一、導入新課:
人類在利用煤,河流的水力發電的同時,也為利用這兩種能源帶來的缺點而煩惱。人們在不斷地努力尋找更科學的發電方法,更合適的能源,隨著科學技術的發展,人們在開發利用新能源方面不斷取得了成功。
二、知道嗎
我們地球上有著豐富除子的能源庫,比如遼闊的海洋,就是最大功率傳輸定理的能源庫之一,波濤洶涌澎湃的海浪,一漲一落的潮汐循環不息的海流。。。都不得是寶貴的能源。再比如核能,一千克鈾全部裂變時,放出的能量超過2000噸優質煤完全烯燒釋放的能量。
看一看:
1、海洋發電
海洋能是無污染的清潔資源,是取之不盡,用之不歆的財富。(1)(2)(3)潮汐能發電 海浪發電 海流發電
2、核電站
3、垃圾電站 板書:
十二、新型發電廠 潮汐能發電 海浪發電 海流發電 核電站 垃圾電站
12、善于聯想
教學目標:
1、通過學習本課,讓學生懂得只有努力學習,平時注意觀察周圍環境,留心身邊的小事物,開動腦筋善于聯想,也能為人類造福。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
讓學生懂得只有努力學習,平時注意觀察周圍環境,留心身邊的小事物,開動腦筋善于聯想,也能為人類造福。
一、導入新課:
“聯想”就是在腦海里從一件事情或者一件物品出發,想到另一件事情或者另一件物品的思維過程。善于聯想可以幫助我們進明創造。
二、看一看
1、從普通信箱聯想到留言信箱。
2、從普通的樓梯聯想到儲物樓梯。
如:一個小朋友看到小狗爬樓梯,聯想輸入到“如果小推車”也能爬樓梯該多好啊,經過不斷地思考,他發明了一種能爬樓梯的小推車。
世界上的許多事物都是互相聯系的,只要善于掌握事物 之間的共同之處和彼此之間的聯系,由此及彼地產生聯想,就能找出解決問題的辦法。
三、想一想
你知道圖上的抓物器是從什么物品中產生聯想而制作出來 的嗎?? 板書:
十三、善于聯想
“聯想”就是在腦海里從一件事情或者一件物品出發,想到另一件事情或者另一件物品的思維過程。善于聯想可以幫助我們進明創造。
14、為了需要
教學目標:
1、通過學習本課,讓學生懂得只有努力學習,平時注意觀察周圍環境,留心身邊的小事物,開動腦筋善于聯想,為了需要也能為發明創造。
2、培養學生的動手能力和想象力;使他們從小養成學科學愛科學的興趣。教學重點、難點:
讓學生懂得只有努力學習,平時注意觀察周圍環境,留心身邊的小事物,開動腦筋善于聯想,為了需要也能為發明創造,也能為人類造福。
一、導入新課:
在發明創造中有一句十分重要,百分正確,千分要牢記的話,那就是“需要是發明創造之母”。母,是個借用詞,意思是“需要”孕育著發明,“需要”萌發出發明,“需要”滋養發明。
人類想有個舒適的環境,夏天不熱,冬天不冷,因此發明了電風扇,取暖器,冷暖空調。
二、看一看
上海時代中學的一位同學把一種知能自控加熱限溫電纜用到她發明的干鞋鉤里,這樣就保持了鞋內的干燥并除去了鞋內產生的異味。
三、給墨水瓶安個家
在課桌的兩邊裝上兩個矩形小箱子,墨水瓶放在里面,可防止墨水瓶被打翻,保持課桌清潔。
四、在擁擠的公交車上,要是沒有足夠的扶手,怎么辦呢?誰來想一想辦法?
五、做一做
小同學因為個子矮,擦黑板時總擦不到上方,要跳起來才能把黑板擦干凈,請你發明一種上下都能擦到的黑板擦。
六、想一想
留心觀察你周圍的生活和學習用品,你可以提出一些什么小發明設想?
板書:
十四、為了需要
“需要是發明創造之母”
小發明設想
十五、快樂的小兔
教學目標:
1、通過本課的學習,使學生從小學科學愛科學。
2、知道做手工快樂的小兔子
3、培養對科學的興趣。教學重點、難點:
1、知道做手工快樂的小兔子
2、培養對科學的興趣。
一、導入:
蹦蹦跳跳的小兔,那活潑可愛的樣子,非常惹人喜愛。下面的活動,移位取代將制作一只快樂的小兔子。
二、準備好
卡紙。20厘米長的鐵絲一根,膠水,美工刀等,三、動手做
一,按圖一尺寸在卡紙板上畫出盒子的展開圖剪下。
二,沿虛線用美工刀輕輕刻出刀痕(注意不要劃斷了。)然后 按要求將它貼合成長方體小合,兩邊先不要封死,以便于工作安裝由軸等內部結構。
一,照圖三在卡紙上畫出小兔。并沿輪廓線將下端兩邊分別向內折成直角。
二,四將鐵絲照明負荷圖四所示彎成由軸。
三,照明負荷圖五將曲軸先穿過小兔下端兩邊的小孔洞,再穿過小合兩個邊孔,最后把小合兩邊粘住。
試一試
搖動物柄,小兔會隨著手柄搖動的節奏又蹦又跳。再為它配上一支歡快的曲子就更熱鬧了
第三篇:新人教語文七上名著復習
初一上名著閱讀閱讀自測及答案
一、《繁星》《春水》
2、《繁星》、3、總的說來,《繁星》、大自然的崇拜和贊頌。三是對人生的思考和感悟。
4、詩集《繁星》、《春水》是人們公認的小詩最高成就,被茅盾稱為、“春水體”。
5明艷;然而當初她的芽兒,浸透了奮斗的淚泉!灑遍了犧牲的血雨”。
6、“墻角的花,你孤芳自賞時。天地便小了。”這一小詩富有意蘊,請你仿造一句同樣富有哲理的句子。溪中的水,你停滯不前時,生命就完了。
7、請你賞析書中你特別喜歡的名句
二《伊索寓言》
1.2.或為主人公。動物寓言部分廣泛采用擬人手法,表現了動物各自的習性。諸如豺狼的兇殘,狐貍的__狡猾__,獅子的威猛,山羊的__怯懦___,都刻畫得栩栩如生,給人留下深刻的印象。
3.融思想性和藝術性于一體。
4.你課外已經讀過伊索寓言了,請你說說下列寓言的主要寓意:
(1)、《狼和小羊》《貓和雞》就以絕妙的諷刺筆法,揭露了當時統治者的殘暴和蠻橫;
(2)、《農夫和蛇》的故事就告誡人們,_對惡人千萬不能心慈手軟_。
(3)、《狐貍和山羊》寫的是掉在井里的狐貍哄騙山羊下井,然后踩著山羊背跳出井底,卻扔下山羊不管的故事,警示人們____做好事也要看對象,以免上當受騙_____。
(4)、《烏龜與老鷹》通過烏龜非要學飛翔不可,結果摔死的悲劇,說明____任何事物都有自己的規律性,不可違背規律____。
(5)、《蚯蚓與狐貍》《鼴鼠》嘲笑____吹牛說大話____,(6)、《駱駝與宙斯》批評___貪得無厭____。
5.《伊索寓言》往往簡潔客觀地敘述一個故事,最后以一句話畫龍點睛的揭示。
6.說說你從書中看到的印象最深的一個故事的內容和寓意
第四篇:新人教(七下)2009-2010
2009-2010七年級數學下學期第一次月考試題答案
一、1.C2.C3.C4.C5.C ;6.A7.C8.A9.C10.C
二、11.80°銳角12.2013.70°14.(7,4)15.105°
16.略17.19.略°
三、21.略
四、22.兩直線平行,同位角相等∠3DG內錯角相等,兩直線平行∠DGA或∠AGD兩直線平行,同旁內角互補110°
26.證明:∵AD//BC
∴∠B=∠EAD(兩直線平行,同位角相等)
∠C=∠DAC(兩直線平行,內錯角相等)
又∵∠ABC=∠C(已知)
∴∠EAD=∠DAC(等量代換)
∴AD平分∠EAC
27.解:∵AB//CD∠1=45°
∴∠D=∠1=45°(兩直線平行,同位角相等)
∠C+∠B=180°(兩直線平行,同旁內角互補)
又∵∠D=∠C(已知)
∴∠C=45°∠B=180°-∠C=135°
28.解:AE//DC(3分)
證明:∵AB//DE
∴∠1=∠AED(兩直線平行,內錯角相等)
又∵∠1=∠2(已知)∴∠AED=∠2(等量代換)
∴AE//DC(內錯角相等,兩直線平行)
第五篇:最新人教新目標8上英語作文
Unit 1
My Vacation to Beijing Wednesday, August 20th Today the weather was hot and sunny.I went to Beijing with my parents.Idid a lots of things there.We visited the Palace Museum and the Great Wall.We also went to Tianan’men Square.There were many people there.Then we went to a Beijing Hutong.It was beautiful.We took some photos.I liked this place because it was interesting.For dinner we had Beijing duck.It was delicious.In the evening, I felt really tired but very happy..1.假如你是林濤,去年夏天去北京度假,參觀過許多地方。以My vacation 為題目,寫一篇70詞左右的短文。內容包括:1,旅游景點(the Great Wall, the Palace Museum, Tian'anmen Square, Beijing hutong).2, 天氣、活動。3,觀點等。
Last summer, I went to Beijing on vacation with my father.The weather was sunny and hot.First we visited the Great Wall.There were a lot of people on the Great Wall.It is really the longest wall in the world.The next day, we visited the Palace Museum and Tian'anmen Square.We took many photos there.We also visited some other interesting places in Beijing.We visited a Beijing hutong, too.We had a great time there.I hope to go there again.Unit 2 根據調查結果寫一篇短文
Activities
Here are the results of the students' activity survey in my class.Everybody takes their exercise for an hour every day.90% of the students eat fruit and drink milk every day.7% of the students eat junk food for 2 or 3 times a week.Nobody drinks coffee.Most students sleep for 8 or 9 hours a day.Unit 3 你和你朋友在外貌和性格方面有什么異同呢?請以“My best friend and I”為題,運用比較級寫一篇英語文章.Should friends be the same or different? For me ,It’s not necessary to be the same.My name is David.My best friend Jeff is quiet different from me.He is shorter and quieter than me.We both like sports ,but he plays baseball better than me ,so he always wins.Jeff works harder and always get good grades.We can talk and share everything.I think my best friend helps to bring out the best in me.We’ll be good friends for ever.關于朋友的短文可以提及:名字、外貌、他喜歡做什么、與你有哪些相同和不同,最好加一些對朋友的看法.My best friend and I Every one needs friends, so do I.I have many friends, but Mary is my best friend.Let me tell you something about her.She is 14 years old.She is tall and thin.She has two big eyes.She is smart.And she is very funny.she likes telling jokes, and she often makes me laugh.We have many things in common.We are both outgoing in our class.We both like sports and math.And we both enjoy playing computer games.However, we also have some differences.She is good at playing tennis, so she always wins in tennis.I am smarter than her, so I always get better grades than her.I think friends are like books, you don’t need a lot of them as long as they are good.So I hope we can be friends forever.請以“My best friend”為題寫一篇介紹你的朋友的短文。短文要運用課文所學的有關句式,把你的朋友和你的長相(包括身高、頭發、眼睛等)、體格(包括強壯強度等)、性格(開朗、文靜等)、學習情況等方面進行比較。詞數70左右。
My best friend My best friend is Li Ming.We are in the same class..He is as old as me, but he is taller and stronger than me.Both of us have black eyes and black hair, but his hair is shorter than mine.Li Ming likes sports.He often exercises after school.He is more outgoing and more athletic than me.But I think I’m smarter than him.Most of my subjects are better than his.Unit 4 上周,我們舉辦了一次“我們城市的一些好場所”的問卷調查,請根據下面的表格所提供的信息寫一篇調查報告,不少于80詞。
A survey of good places in our city Last week we did a survey about good places in our city.And this is what we learned.Most of the high schools are good, and the No.10 High School is the best in our city.It has the best teachers and it's the most beautiful.People's Hospital is the best of all.It has the most comfortable beds and the friendliest service.Modern Cinema is the best.It has the biggest screens.The best clothing store in our city is Xiwang Clothing Store.It has the best quality and it's the most popular.As for radio station, most young people think Hefei 168 FM is the best radio station.It has the latest news and the most interesting music.Unit 5 請根據下列表格內容寫一篇他們各自的愛好情況字數在60詞左右.Today ,I asked my family about movies.Some of their answers are very interesting.Here are their likes and dislikes.My sister likes cartoons very much, but she can’t stand action movies.My mother can’t stand action movies, either.She likes comedies.My father dislikes sitcoms ,but he likes action movies.My brother likes action movies ,too.He can’t stand cartoons.Unit 6.新學期要到了,寫一篇關于學期的計劃,講述一下自己打算在新的學期要做些什么?提示:可以寫自己在學習,健身,娛樂,培養業余愛好等方面的計劃或打算.New Year’s Resolutions New year is coming.I’m going to do a lot of things next year.First, I want to improve my Chinese, so I’m going to practice it very often and have many conversations with my friends.Next, I want to be healthier, so I’m going to do sports every day such as swimming, running and so on.At the same time, I’m going to eat less junk food.Finally, I want to join the dancing club, so I’m going to practice dancing twice a week.I hope my resolutions can come true in the coming year.本學期計劃打算
This term I should study harder.I am good at math, physics and science.However, my English is not good.So on the one hand, I think I should ask the teacher for help.On the other hand, I will learn from my good friend.His English is good.Maybe he would like to help me.My teacher said my compositions were not good.So I should read more useful books after class.I believe I will do well in English.On the other way, I should take more exercise, this will make me strong and healthy.I like playing ball games.After class I should make more friends, because the more we are together, the happier we will be My New Year’s Resolutions
Here are my plans for the new school year.I’m going to study harder to get better grades and make more friends.I’m going to improve my English.To keep healthy, I’m going to eat healthy food and get lots of exercise.I’m going to eat more vegetables and fruit and have less junk food.Also, I like playing the guitar, so I’m going to take my guitar lessons every weekend.寒假即將來臨,請根據一下提示寫一篇短文,談談你的寒假計劃。
1、好好休息和放松;
2、讀書,因為讀書既能開闊視野,還能學到很多知識;
3、陪父母聊天,幫他們做家務;
4、參加社會活動,認識更多的人。要求:
1、詞數:80詞左右
2、可圍繞主題適當發揮 參考詞匯:knowledge 知識; social activities 社會活動 范文: The winter holiday is coming.I’m going to do what I want to do.First, I’m going to have a good rest and relaxation.I will read some good books.Reading books is useful because it can not only open up my mind but also help me get more knowledge.Next, I’m going to spend more time talking with my parents.I will also try my best to help them do some housework.Then, I’m going to take part in social activities so that I can get to know more people.What do you think of my holiday plan? I hope you will have a happy winter holiday.My life in ten years In ten years, I think I'll be a reporter.As a reporter, I think I'll meet lots of interesting people.And I will also travel all over the world.I'll live in Beijing because I went there last year and fell in love with it.And I will keep a pet pig, because I like it very much.I will live in an apartment with my parents.This is my life in ten years, I think I will be very happy in the future.七、請以“未來的學校生活”為主題,寫一篇英語短文。要求:靈活運用一般將來時。
School life in the future I think school life in the future will be more colorful and interesting.We students will have classes only in the morning.We won’t have homework after school.We will have more free time to take part in all kinds of(各種各樣的)activities in the afternoon.For example, we will play sports, visit the museums and go to the movies.If we are ill, we will study at home.We will listen to the teacher on the Internet.My hometown in 20 years I think my hometown will be very different in 20 years.My hometown will be cleaner and more beautiful.There will be less pollution and we will see the blue sky.The water will be cleaner and the air will be fresher.There will be more people.People will be richer and happier.I love my hometown.I hope it will become more and more beautiful.What will our life be like in the future? I think our life in the future will be better and better.There will be more tall buildings and most people will live in big houses.There will be fewer cars and more buses.There will be more trees and less pollution in the future.As for education, I think there will be fewer schools in the future.Most students will study at home on computers.How wonderful the life in the future will be!My future Everyone dreams about the future.I also have a dream about my life in 20 years.I will live in Shanghai with my families because we like it very much.It will be more beautiful.I will teach in a middle school.I will be a good English teacher.I will love my students, and my students will love me, too.We will be good friends.As a teacher, I will get on well with my students.I will do sports with my students every day.Swimming and running will be my favorite sports.I will be healthy and strong.There will be more robots everywhere.They will help us do many things.I believe we will have more time to study and play.This is my future dream.I ‘m sure I will have a more wonderful life in 20 years.I will work hard to make my dream come true.What do you think of it? 2.每個人對未來都充滿憧憬,請談談你心目中未來的理想工作,以
“My Dream Job”為題
1.What is your dream job? 2.Where would you like to work? 3.Why do you like your dream job? 4.How are you going to work?
My dream job Everybody has a dream job.Do you want to know what I want to be in the future? Well, I’m going to be an English teacher when I grow up.My English was not good.Sometimes my classmates laughed at me.My English teacher Mrs.Wang helped me a lot.I want to be a teacher like her.I’m going to study education and learn how to teach children.I’m going to start when I finish high school and college.I think Chengdu is where I want to work,so I’ll work in Chengdu when I grow up.I hope my dream will come true one day.And What’s your dream job?
My dream job”為題,寫一篇80詞左右的短文,介紹自己對未來理想職業的打 算
My Dream Job
Everybody has a dream job.Do you want to know what I want to be in the future? Well,I want to be a singer.Because I love singing very much.And I think that I can sing on the stage(舞臺).I will move to New York and be a singer there。And I will sing my favorite English songs there.Although it is a tiring job, I love it.Because when I am sad, I can sing songs to be happy and I will become very popular.That’s so interesting and exciting.For my dream job, I will sing every day and sing well.I hope that day come soon , I can’t wait!How about you? What’s your dream job?
I have a dream, my dream is to be an English teacher.The reason for this is that I like English, and also I like my English teacher very much, so I want to be an English teacher like him.I will love my job, and love each of my students.I will teach my students very well, and tell them many interesting stories and teach them to learn beautiful English songs.In order to achieve my dream, I think I should start from now on.First of all, I should learn hard, not only English, but also other subjects.I need to go to college to get a good education.Next, I should learn how to communicate and get along well with other people, especially children.Then, I will watch and learn my teachers' teaching ways and skills.I hope my dream will come true.示以My Dream Job為題寫一篇短文(unit 6)提示:(1)想成為一名記者(2)打算給報紙寫文章(3)高中以后想去北京上大學(4)想在一家電臺工作并環游世界
When I grow up, I'm going to be a journalist.Next year, I'm going to write articles for magazines and newspapers.I'm going to a university in Beijing after high school.Maybe I'm going to find a part-time job and save some money.Next, I’m going to work for a TV station as a journalist.Then I am going to travel all over the world.Unit 8 你知道感恩節這天,人們會吃什么嗎?請根據本單元知識敘述一下這種食物的制作過程.How to make turkey Here is one way to make turkey for a Thanksgiving dinner.First, mix together some bread pieces, onions, salt and pepper.Next, fill the turkey with this bread mix.Then, put the turkey in a hot oven and cook it for a few hours.When it is ready, place the turkey on a large plate and cover it with gravy.Finally, cut the turkey into thin pieces and eat the meat with vegetables like carrots and potatoes.Do you know how to make a beef sandwich? Now, let me tell you.First, put a spoon of cheese on a piece of bread.Next, cut up a green pepper and an onion.Add these to the bread.Then, put some mushroom and 2 pieces of beef on the bread.Finally Put another piece of bread on the top.Now you can enjoy it.It’s very delicious.九、你寫一篇制作爆米花(popcorn)的小短文。注意使用first,next,then, finally等表示過程的詞
How to make popcorn I like popcorn very much.I learned from my mother how to make popcorn.Now let me show you the ways.First you put the popcorn into the popcorn machine.Next, turn on the machine.Wait for several minutes.Then pour the popcorn into the bowl.And put some salt on the popcorn.Finally you can eat the popcorn.Unit 9 假如你的好友邀請你去參加生日聚會,但因為你下周的日程已經排滿,不能前往。請根據提示給她回信婉言謝絕,并表達你的謝意。Hi Ann, Thank you for your invitation.I am sorry I can't come to your birthday party this week.I am really busy.On Monday, I am going to the movies with my friends.On Tuesday, I am going to visit my aunt.On Wednesday, I have to help my mother.On Thursday, I am going to my sister's birthday party.On Friday, I am going to Ning Bo on vacation with my parents.I have bought a nice gift for you.I hope you will like it.I hope you will have a good time.yours Candy
根據提示寫一封60-80字的信。Tom 邀請Li Ping 參加他這周日的生日宴會,但Li Ping的父母出差要到下個月回來,奶奶又臥病在床,需要人照顧。再說英語考試即將來臨,因此,無法前去參加生日宴會。Li Ping感到很抱歉,只好寫信辭謝。Dear Tom, Thank you very much for inviting me to your birthday party.I'd love to go but I can't..My parents are out on business.They are coming back next month.And now I have to look after my grandma because she is ill in bed.And I also need to study for my coming English exam.I'm very sorry but I can't go to your party.Thank you for asking me.I hope you can have a good time.Li Ping Hi Henry, Thanks for inviting me to go climbing next week.I’m sorry, I ‘m not available.I have a really busy week.Today I am going shopping in the supermarket, and tomorrow I will go to Mary’s birthday party.On Tuesday I’ll go to the doctor.On Wednesday I am going to play with the school team and I will have a science test on Thursday.I will go to the movies with some friends on Friday.On Saturday I will have to do some washing.Oh, it is late.I must stop now.I hope you will have a good time.Write back soon.Yours, Kate
Unit 10 你以后可能會有很多錢,想一想,如果你有了錢,你會用它做什么?以If I have a lot of money為題寫一篇60詞左右的短文.If I have a lot of money If have a lot of money, I'll travel round the world and I'll stay at the best hotels.If I have a lot of money , I will buy a big house with a beautiful garden for my parents , I want them to live a happy life.Also, I will buy a sports car for my father and give my mother many fashion clothes.If I have a lot of money , I will give some money to charities and help the poor students.So they can go to school and get a good education again.I am sure, one day, my dream will come true.If I have a lot of money If I have a lot of money, I will have the chance to do what I want to do.It is best to do good things with the money.So I think I’ll give some money to charities to help the people in need.I’ll try my best to help people who are in trouble.Then, I will buy a big house with a garden and a swimming pool for my parents, so they will live a happy life.I’m sure I will enjoy a better life.If I have a lot of money If I have a lot of money, I will do something important.My dream will come true.Of course, I can do a lot with the money.I’ll help the old and the poor.Besides, I’ll give money to the charities or schools and help those poor children who can’t go to school.I hope they will change their lives in the future with the knowledge.At the same time, I think I’ll buy a big house for my parents, and help them enjoy their lives.In a word, I can do a lot of wonderful things and make contribution to our country.I will try my best to make my dream come true.If I am a teacher
I want to be a teacher when I grow up.If I become a teacher, I'll try my best to teach my students well In class, I'll be strict with them.After class, I'll play with them.If they are in need, I'll help them.I'm sure I'll be a good friend of them and a good teacher.I hope I'll be a teacher when I grow up.I believe there is nothing difficult in the world if you put your heart into it.Do you believe me
If I am a teacher, I will be very happy.I like students and the job.In class, I’ll discuss some questions with the students.I’ll be glad to help them.I’ll encourage them to take part in every activity.I think each of them is a good student and I also believe them.After class, we’ll play sports together, have interest groups, talk about the interesting topics, and we’ll have a picnic on weekends.I think we’ll have a great time and the students will grow up healthily.How to keep healthy If we want to keep healthy, we must have a good habit.We should get up and go to bed early and sleep at least eight hours every day.Do more exercise, such as walking, swimming, playing balls and so on.We should also eat healthy food—more fruit and vegetables and less meat.If you don’t feel well, you’d better see a doctor at once.And we should wash our hands before meals and drink enough boiled water every day.It’s necessary for our health.We should not throw litter about or smoke.It’s also very important.從飲食,睡眠和運動幾方面談談怎樣可以保持身體健康。
Health is one of the most important things for us.Without a good health, we can’t do anything.So we all want to keep healthy.But how? If you want to be healthy, you must have a good diet.You shouldn’t have too much hot or sweet food with much fat.They are all bad for your health.Instead, you should have vegetables and fruit to keep yourself healthy.You should also sleep well.A student should sleep at least 8 hours a day.Besides, it is necessary to take more exercise , too.You should take more exercise to make yourself stronger and healthier.Since health is so important, we should try our best to keep healthy.四、我最會喜歡的電視節目:寫出節目名、敘述內容以及喜歡的原因
My favorite TV show My favorite TV show is China’s Got Talent.The talent show tries to look for the best singers, the most exciting magicians, the funniest actors and so on.All kinds of people join the show to show their talents.Some people are truly talented.When you watch the shows, you can play a role in deciding the winner.The winner usually gets a good prize.I like it because it gives people a way to make their dreams come true.五、影評:需注意時態;介紹電影類型、主人公、故事大意、以及個人看法。The Lion King The Lion King is a great movie.I like it very much.It’s a cartoon.It ‘s a story of Simba.Simba’s father was the king.But his uncle Scar killed his father.When Simba grew up, he came back to the forest and became the true king of the forest.Simba is hard-working, and he has many good friends.He is also kind so he can becomes the true king.I think it is fantastic.And if you plan to watch a movie, choose The Lion King.