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請(qǐng)聽四段對(duì)話.完成第5至第8小題. No.5. Woman: Can I help you, sir? Man: Yes, please. Some bread. No. 6. Woman: Jim, are you taller than your mother? Man: Yes, but my father is the tallest. No. 7. Woman: Do you usually come to school by bike? Man: Yes, but I came to school on foot this morning. No. 8. Woman: What are you going to do this Saturday morning? Man: Nothing much. Why? Woman: Would you like to go shopping with me? Man: I’d love to. 請(qǐng)聽一段對(duì)話.完成第9和第10小題. (Sounds of knocking on the door) Man: Come in, please. Good morning, Mary. Girl: Good morning, Dr. Smith. Man: What’s your trouble, Mary? Girl: I don’t feel well today and I have a headache. Man: I’m sorry to hear that. Now, open your mouth and say “ah . Girl: Ah-ah! Man: You’ve only got a cold. Go and get some medicine and you will be all right soon. Girl: Can I go to school this afternoon? I’ll have an English test tomorrow morning. Man: Sure! You can go to school as usual, but you’d better go to bed earlier than before. Girl: Thank you, Doctor! 請(qǐng)聽一段對(duì)話.完成第11和第12小題. Boy: Good afternoon. Woman: Good afternoon. Can I help you? Boy: Yes, my name is Jim. I want to borrow some books, but this is the first time. What should I do? Woman: First, you should get a library card. Boy: Do I have to pay for it? Woman: It is free for students under 18 years old. I’m sure you are under 18. Right? Boy: Yes, I’m only ten years old. Woman: But you should bring a letter from your teacher to show your name and your school. Boy: I see. Thank you very much. Woman: My pleasure. 請(qǐng)聽一段對(duì)話.完成第13至第15小題. Woman: Have you read today’s paper? Man: No, I haven’t seen it yet. Why? Woman: I really like the story on the front page. Man: Really? What’s it about? Woman: It’s about some lovely pandas. So interesting! Man: Well, I guess I will have to read it later in the day. Woman: Why later in the day? Haven’t you got the paper yet? Man: Well, I won’t get it until early in the evening. Woman: That’s terrible. I get it at nine every morning. Man: How do you do that? Woman: I buy it on my way to work. Man: I should do that, too. Maybe I can get it at eight in the morning. 請(qǐng)聽一段獨(dú)白.完成第16至第18小題. Good afternoon, everybody. Welcome to our school. You’re lucky to be the students of this school. But at the beginning of the school, you may meet some difficulties. In the first few months, spend some time walking around the school and find out what it is like. Do your best to get used to the living here and get to know your teachers and classmates. Try to understand what you are expected to do at school. This will help you become clear about your own plan. During this time you have to study hard to pass the exams. But what's more important for you is to learn how to learn. Think about what you want from the school and try your best to make your dreams come true. You may have some problems in your studies. Learning is not always a pleasant journey. Some of you may find your studies are not exciting and think of stopping it. At this moment, just think it over before you make the decision. For learning is important for you. It will help you make your future life better. Our school can answer your real learning if you can make up your mind to go through with it. This is what I like to say to you now. Thank you. 請(qǐng)打開第Ⅱ卷.看第一大題聽力試題.該試題需要在第Ⅱ卷第一大題的相應(yīng)位置上作答. 第Ⅱ卷 查看更多

 

題目列表(包括答案和解析)

某合作學(xué)習(xí)小組欲用生石灰制取氫氧化鈉固體,他們將少量生石灰放入燒杯中,再向其中加入一定量碳酸鈉溶液,充分反應(yīng)冷卻后過濾、洗滌得到固體A和溶液B.請(qǐng)你寫出發(fā)生反應(yīng)的化學(xué)方程式  

請(qǐng)你與小組同學(xué)共同完成以下探究:

【查閱資料】NaOH、Ca(OH)2的溶解度

溫度(℃)

0

20

40

60

80

100

NaOH溶解度(g)

31

91

111

129

313

336

Ca(OH)2溶解度(g)

0.19

0.17

0.14

0.12

0.09

0.08

【提出問題1】固體A中的成分是什么?

【猜想與假設(shè)1】

甲同學(xué):只有CaCO3

乙同學(xué):CaCO3,Ca(OH)2

乙同學(xué)猜想可能含有的Ca(OH)2理由是  

【實(shí)驗(yàn)與探究】甲、乙同學(xué)為了驗(yàn)證各自的猜想,分別進(jìn)行了實(shí)驗(yàn):

實(shí)驗(yàn)內(nèi)容

實(shí)驗(yàn)現(xiàn)象

實(shí)驗(yàn)結(jié)論

甲同學(xué):取少量固體于試管中,再加入稀鹽酸.

有氣泡產(chǎn)生

自己的猜想正確

乙同學(xué):取少量固體于試管中,加水充分振蕩,過濾,向?yàn)V液中滴加 酚酞溶液 

溶液由無色變?yōu)榧t色

自己的猜想正確

【反思與評(píng)價(jià)】小組同學(xué)討論后認(rèn)為,甲同學(xué)的實(shí)驗(yàn)不能證明他的猜想,理由是

 ;

結(jié)合甲、乙兩同學(xué)的實(shí)驗(yàn)?zāi)茏C明乙同學(xué)的猜想正確,因此小組同學(xué)確定了固體A的成分.

【提出問題2】溶液B中溶質(zhì)的成分是什么?

【猜想與假設(shè)2】

丙同學(xué):NaOH,Na2CO3

丁同學(xué):NaOH,Ca(OH)2

戊同學(xué):NaOH

【表達(dá)與交流】結(jié)合對(duì)固體成分的探究,同學(xué)們經(jīng)過討論確定了丁同學(xué)猜想正確,

理由是 

該小組同學(xué)欲將溶液B加熱濃縮,加熱不久,溶液出現(xiàn)渾濁,只好停止加熱,請(qǐng)解釋加熱時(shí)溶液出現(xiàn)渾濁的原因  

該小組同學(xué)立即變換方案,向溶液B中繼續(xù)滴加碳酸鈉溶液至不再產(chǎn)生沉淀為止,過濾,再將濾液加熱蒸發(fā),冷卻結(jié)晶,過濾得純凈的氫氧化鈉固體.

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某合作學(xué)習(xí)小組欲用生石灰制取氫氧化鈉固體,他們將少量生石灰放入燒杯中,再向其中加入一定量碳酸鈉溶液,充分反應(yīng)冷卻后過濾、洗滌得到固體A和溶液B.請(qǐng)你寫出發(fā)生反應(yīng)的化學(xué)方程式  

請(qǐng)你與小組同學(xué)共同完成以下探究:

【查閱資料】NaOH、Ca(OH)2的溶解度

溫度(℃)

0

20

40

60

80

100

NaOH溶解度(g)

31

91

111

129

313

336

Ca(OH)2溶解度(g)

0.19

0.17

0.14

0.12

0.09

0.08

【提出問題1】固體A中的成分是什么?

【猜想與假設(shè)1】

甲同學(xué):只有CaCO3

乙同學(xué):CaCO3,Ca(OH)2

乙同學(xué)猜想可能含有的Ca(OH)2理由是  

【實(shí)驗(yàn)與探究】甲、乙同學(xué)為了驗(yàn)證各自的猜想,分別進(jìn)行了實(shí)驗(yàn):

實(shí)驗(yàn)內(nèi)容

實(shí)驗(yàn)現(xiàn)象

實(shí)驗(yàn)結(jié)論

甲同學(xué):取少量固體于試管中,再加入稀鹽酸.

有氣泡產(chǎn)生

自己的猜想正確

乙同學(xué):取少量固體于試管中,加水充分振蕩,過濾,向?yàn)V液中滴加 酚酞溶液 

溶液由無色變?yōu)榧t色

自己的猜想正確

【反思與評(píng)價(jià)】小組同學(xué)討論后認(rèn)為,甲同學(xué)的實(shí)驗(yàn)不能證明他的猜想,理由是

 ;

結(jié)合甲、乙兩同學(xué)的實(shí)驗(yàn)?zāi)茏C明乙同學(xué)的猜想正確,因此小組同學(xué)確定了固體A的成分.

【提出問題2】溶液B中溶質(zhì)的成分是什么?

【猜想與假設(shè)2】

丙同學(xué):NaOH,Na2CO3

丁同學(xué):NaOH,Ca(OH)2

戊同學(xué):NaOH

【表達(dá)與交流】結(jié)合對(duì)固體成分的探究,同學(xué)們經(jīng)過討論確定了丁同學(xué)猜想正確,

理由是 

該小組同學(xué)欲將溶液B加熱濃縮,加熱不久,溶液出現(xiàn)渾濁,只好停止加熱,請(qǐng)解釋加熱時(shí)溶液出現(xiàn)渾濁的原因  

該小組同學(xué)立即變換方案,向溶液B中繼續(xù)滴加碳酸鈉溶液至不再產(chǎn)生沉淀為止,過濾,再將濾液加熱蒸發(fā),冷卻結(jié)晶,過濾得純凈的氫氧化鈉固體.

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請(qǐng)回答下列有關(guān)金屬的問題.

(1)如圖1是某探究鐵生銹條件的實(shí)驗(yàn)裝置.一段時(shí)間后,能觀察到U型管液面左端高,右端低,說明鐵釘生銹后使試管內(nèi)氣壓  
(2)鐵在一定條件下能轉(zhuǎn)化為鐵銹,鐵銹(主要成分是氧化鐵)怎樣轉(zhuǎn)化為鐵呢?用化學(xué)方程式表示                   
(3)圖2所示的四個(gè)裝置中,不屬于連通器的是     (填字母序號(hào)).

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6月5日是世界環(huán)境日,今年的主題是“海洋存亡,匹夫有責(zé)”,開發(fā)海洋,維持海洋的可持續(xù)發(fā)展是每個(gè)地球公民的神圣職責(zé).請(qǐng)回答下面關(guān)于海洋的幾個(gè)問題:
問題一:今年5月,我國浙江沿海發(fā)生大面積的“赤潮”,造成養(yǎng)殖業(yè)重大損失.赤潮的發(fā)生主要是與因?yàn)樵孱惖寞偪裆L,與藻類瘋長的密切相關(guān)的元素是______和______.(填元素符號(hào))


問題二:海水中資源豐富,含量最多的金屬陽離子是______(填符號(hào)),含量最多的分子是______(填符號(hào)),海水中除含有大量的氯化鈉外,還有氯化鎂、氯化鈣等物質(zhì),則下列結(jié)構(gòu)示意圖所表示的微粒一定在海水中含有的是______.(填序號(hào))
問題三:我國舟山鹽場海水曬鹽的原理是______.
A、氯化鈉的溶解度受溫度影響較大 B、因氯化鈉溶解度受溫度影響不大,故采取蒸發(fā)水分的方法所得粗鹽中主要含泥砂、氯化鎂、氯化鈣等雜質(zhì),現(xiàn)對(duì)其進(jìn)行提純,主要操作流程如下:

(1)操作①的名稱是______,操作②的名稱是______.
(2)A溶液是______,B溶液是______.(選擇合適序號(hào)填空)
a、Na2CO3     b、K2CO3    c、H2SO4   d、HCl
問題四:經(jīng)勘察,深海下含有豐富的“可燃冰”,可滿足人類1000年的能源需要.該物質(zhì)是一種晶體,晶體中平均每46個(gè)水分子構(gòu)建成8個(gè)籠,每個(gè)籠可容納1個(gè)CH4分子或1個(gè)游離H2O分子.若晶體中每8個(gè)籠只有6個(gè)容納了CH4分子,另外2個(gè)籠被游離H2O分子填充,則天然氣水合物的平均組成可表示為______.
A、CH4?14H2O  B、CH4?8H2O  C、CH4?(23/3)H2O   D、CH4?6H2O
若該水合物可表示為CH4?nH2O,則其與氧氣完全燃燒的方程式如下,請(qǐng)將括號(hào)中的化學(xué)計(jì)量數(shù)補(bǔ)充完整:
CH4?nH2O+2O2數(shù)學(xué)公式CO2+______H2O.
問題五:海水淡化是國際上研究的熱點(diǎn)問題,我國科學(xué)家在利用高分子膜進(jìn)行海水淡化的研究上取得了一些成績.如圖1,左側(cè)為海水,右側(cè)為經(jīng)過一段時(shí)間后由左側(cè)經(jīng)高分子膜滲透得到的淡水,分析高分子膜在海水淡化過程中的作用______.

問題六:如圖2為某學(xué)生制作的一種家用環(huán)保型消毒液發(fā)生器:原理是電解飽和氯化鈉溶液,制得的消毒液有較強(qiáng)的殺菌能力,該反應(yīng)是利用氯化鈉和水在電解條件下生成NaOH、H2和Cl2,請(qǐng)完成化學(xué)方程式.
______.
該消毒液中起消毒作用的物質(zhì)是NaClO(次氯酸鈉),它是由氯氣和NaOH進(jìn)一步反應(yīng)制得的,方程式為:2NaOH+Cl2=NaCl+NaClO+H2O.請(qǐng)模仿寫出Cl2與消石灰作用制取漂白粉的化學(xué)反應(yīng)方程式:______.

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(1)如圖1所示a、b、c、d四個(gè)點(diǎn),表示可燃物容易著火的點(diǎn)是______點(diǎn)(填字母序號(hào)).

(2)請(qǐng)根據(jù)如圖2反應(yīng)的微觀示意圖分析:
參加反應(yīng)的化合物A與化合物B的分子個(gè)數(shù)比為______,生成物中單質(zhì)分子與化合物分子的個(gè)數(shù)比為______.
(3)將一定質(zhì)量的氯酸鉀(不含催化劑)置于試管中加熱一段時(shí)間,冷卻后測得所得固體
中氯元素的質(zhì)量分?jǐn)?shù)為35.5%,則反應(yīng)中已分解的氯酸鉀的質(zhì)量分?jǐn)?shù)為______%.
(4)請(qǐng)根據(jù)圖3所示回答問題:
①甲圖中R物質(zhì)在室溫(20℃)時(shí)的飽和狀態(tài)為D點(diǎn),40℃時(shí)的飽和狀態(tài)為A點(diǎn),現(xiàn)將甲圖中的R溶液從A狀態(tài)變到B狀態(tài),請(qǐng)?jiān)O(shè)計(jì)并簡述兩個(gè)簡單的實(shí)驗(yàn)操作途徑:a.______;b.______;c.A狀態(tài)由兩種不同途徑變到B狀態(tài)時(shí),溶液的溶質(zhì)質(zhì)量分?jǐn)?shù)是否相等______(填“是”或“否”).
②乙圖是表示M、N兩種物質(zhì)飽和溶液的溶質(zhì)質(zhì)量分?jǐn)?shù)隨溫度變化的曲線.現(xiàn)分別向50g M、80g N固體中各加入150g水,并加熱至完全溶解,同時(shí)各蒸發(fā)掉50g水,冷卻至t℃,下列分析正確的是______(填序號(hào),多選、少選、錯(cuò)選均不給分).
a.只有N析出晶體;  b.M、N兩種溶液的溶質(zhì)質(zhì)量分?jǐn)?shù)相等;
c.只有M析出晶體;  d.M、N均有晶體析出;
e.M、N兩種物質(zhì)的溶解度相同.

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