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科目: 來源: 題型:

現(xiàn)有A、B、C、D四種常見的物質(zhì),它們之間有下圖所示的轉(zhuǎn)化關(guān)系。已知A常溫下為液體,A、B兩種物質(zhì)的組成元素完全相同,D是黑色固體。據(jù)此推斷:

(1)A是___________,B是___________;
(2)寫出有關(guān)反應(yīng)的化學(xué)方程式:
B→C_______________________________、
D→A_______________________________。

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科目: 來源: 題型:閱讀理解

完型填空(共20小題;每小題1分,滿分20分)
閱讀下面短文,掌握其大意,然后從四個選項(A、B、C和D)中,選出最佳選項。
"Hey, Tahlia! How's the model?"
I had just taken a bite of my hot dog __21__ I heard a familiar voice yelling at me from across the crowded school yard. I saw a group of popular girls who were all __22__.
"What kind of __23_ are you going to do? An ad for a Frankenstein movie?" More laughter. My stomach twisted into a tight knot. How could they humiliate (羞辱) me like this, __24__ the entire school? As I walked into the cafeteria, I __25__ the dark scars on my right hand.
At 9 months old, I knocked over a tea pot and dumped boiling water allover my hands and stomach. My parents __26__ me to the hospital, but I had to have skin graft (移植) operation. I was in so much pain! But what __27__ me most were the cruel things people said about how I looked, __28__ that day at lunch.
The girls were being supermean to me because they'd heard I was considering doing some modeling. A close friend had suggested that I shouldn't let my scars limit me and that I might __29__ a good model.
But after that __30__ at school, I was sure I'd made a huge mistake. Upon arriving home, I covered the mirror with a blanket, fell on my bed and sobbed.
The next day, I __31__ myself to go to school. At lunch my best friend Jesse tried to encourage me: "You can't __32_ forever, Tahlia. So what if you have a few scars? Just go outside and show them that you're just as good as they are." Although I knew he was right, I couldn’t __33__ standing up for myself like that.
However, that night as I sat on the bed, my friend's words replayed in my mind. I'm __34__ hiding from myself, I thought. How stupid! Slowly, I stood up, walked over to the __35__, and tossed the blanket aside. There, in the mirror I saw a slim, dark-haired, blue-eyed girl, looking just fine, __36__ with a few scars.
The next day I wore a comfortable T-shirt to school. What's more, I had lunch outside the cafeteria, __37__ beside those mean girls. They were shocked that I should dare to walk into their territory. I felt __38_ too—free and happy.
Sometimes people still look at me strangely. They __39_ and stare, but I don't let it get to me. I have applied to several modeling companies, and at least one company is considering me for jobs. Maybe I'll never __40_ posing on the runway, but I do know one thing: I'm done.
【小題1】
A.a(chǎn)s B.when C.while D.before
【小題2】
A.a(chǎn)pplauding B.cheering C.laughing D.quarreling
【小題3】
A.modeling B.writing C.drilling D.a(chǎn)cting
【小題4】
A.in spite of B.in view of C.in terms of D.in front of
【小題5】
A.looked into B.searched for C.wondered aboutD.glanced at
【小題6】
A.presented B.sent C.rushedD.handed
【小題7】
A.hurtB.beat C.disappointed D.puzzled
【小題8】
A.for B.like C.on D.a(chǎn)fter
【小題9】
A.impressB.make C.consult D.defeat
【小題10】
A.effect B.phenomenon C.challenge D.scene
【小題11】
A.forced B.expected C.reminded D.preferred
【小題12】
A.a(chǎn)pologize B.beg C.hide D.complain
【小題13】
A.consider B.imagine C.a(chǎn)ppreciate D.resist
【小題14】
A.hardly B.ever C.even D.gradually
【小題15】
A.blanket B.bed C.chair D.mirror
【小題16】
A.while B.though C.but D.because
【小題17】
A.right B.still C.therefore D.a(chǎn)nyhow
【小題18】
A.sensitive B.uncomfortable C.different D.tense
【小題19】
A.compare B.a(chǎn)ssociate C.wave D.whisper
【小題20】
A.give up B.end up C.put up D.set up

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科目: 來源: 題型:

3分)人類的生產(chǎn)和生活離不開金屬。
(1)鐵生銹的條件是鐵與____________________直接接觸;
(2)銅制品如果長期暴露在空氣中也會生銹。已知銅銹的化學(xué)式為Cu2(OH)2CO3,試判斷銅生銹除滿足鐵生銹的上述條件外,還需要空氣中的______________;
(3)在生活中經(jīng)常用一些鋁制品代替鐵,鋁耐腐蝕的原因是__________(選填序號)。
A.鐵比鋁金屬活動性弱
B.鋁與氧氣反應(yīng)在其表面生成致密的氧化物保護膜
C.常溫下,鋁不與稀鹽酸、稀硫酸等稀酸溶液反應(yīng)

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(10分)下表是某同學(xué)實驗報告的部分內(nèi)容:
實驗序號
反應(yīng)物甲
反應(yīng)物乙
實驗現(xiàn)象
化學(xué)方程式

碳酸鈉溶液
氫氧化鈣溶液
產(chǎn)生白色沉淀
 

碳酸鉀溶液
氯化鈣溶液
 
K2CO3 + CaCl2 ="=" 2KCl + CaCO3

碳酸鈣
稀鹽酸
有氣泡產(chǎn)生
 
(1)請在表中的空白處補全有關(guān)內(nèi)容;
(2)表中三個反應(yīng)都是探究___________的化學(xué)性質(zhì);
(3)實驗①和實驗②能發(fā)生反應(yīng)的共同原因是:“反應(yīng)物甲”中的____________和“反應(yīng)物乙”中的______________相互結(jié)合成_______________;
(4)試舉一例說明反應(yīng)③的實際應(yīng)用______________________________。

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思思同學(xué)總結(jié)出酸、堿、鹽相互間的反應(yīng)關(guān)系如下圖所示。只要選取恰當?shù)姆磻?yīng)物,則反應(yīng)①~反應(yīng)④均可生成BaSO4

(1)圖中的酸是____________,堿是___________;
(2)反應(yīng)③的化學(xué)方程式可能是:_____________________________;
(3)圖中四個反應(yīng)均屬于____________反應(yīng),發(fā)生反應(yīng)時的共同現(xiàn)象是_________________。

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下圖是實驗室制取和收集氣體的裝置圖。

(1)小紅用高錳酸鉀制取氧氣,應(yīng)選用的氣體發(fā)生裝置是________,反應(yīng)的化學(xué)方程式為____________________________________________。若用圖E裝置收集產(chǎn)生的氧氣,應(yīng)等到____________________________時,再把導(dǎo)氣管插入集氣瓶口;
(2)小麗用圖B裝置制取氫氣,請指出圖中的錯誤_______________________。收集氫氣應(yīng)選用的裝置是________________。

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科目: 來源: 題型:

(4分)下圖中的A裝置是實驗室中集洗氣、集氣、貯氣等于一體的多功能裝置。

(1)若用該裝置干燥氫氣,則瓶內(nèi)所盛物質(zhì)是______。實驗時,氫氣應(yīng)從________(填“左”或“右”)端的導(dǎo)氣管通入;
(2)醫(yī)院給病人輸氧也用到類似圖A的裝置。氧氣由左端導(dǎo)管口通入,而病人的吸氣管則與右端導(dǎo)管口相連。你認為該裝置的作用是___________________________(寫一點即可);
(3)要檢查圖A裝置的氣密性,可采用圖B所示的裝置。當緩慢拉動注射器的活塞時,如果裝置氣密性良好,可觀察到的現(xiàn)象是_______________________________。

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(5分)粗鹽是含有較多可溶性雜質(zhì)(如氯化鎂和氯化鈣等)和不溶性雜質(zhì)(如泥沙等)的氯化鈉。為提純粗鹽,同學(xué)們經(jīng)過了①蒸發(fā)結(jié)晶、②溶解、③過濾、④計算產(chǎn)率等步驟。
(1)實驗過程中,合理的操作步驟為_______________(用序號填空);
(2)實驗過程中使用次數(shù)最多的儀器是__________;
(3)經(jīng)過上述操作得到的精鹽屬于___________(填“純凈物”或“混合物”);
(4)實驗結(jié)束后,有4個小組分別展示了計算的精鹽產(chǎn)率:
組別
1
2
3
4
精鹽產(chǎn)率
91%
69%
73%
75%
老師對各組的評價是:第1組結(jié)果偏高,其他組結(jié)果都偏低。于是各組分別討論本組
的誤差,所找原因合理的是第___________組。(2分)
第①組:量水時眼睛位置太高,造成俯視
第②組:稱量精鹽時誤將精鹽放在右盤
第③組:沒有蒸發(fā)干,精鹽中仍然有水分
第④組:燒杯里的食鹽未溶解完就開始過濾

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科目: 來源: 題型:

(10分)做化學(xué)實驗時,實驗臺上的藥品應(yīng)分類有序地擺放。在一次化學(xué)興趣小組活動中,實驗臺上擺放了下列藥品,其中一試劑瓶的標簽破損(見下圖)。

(1)欲比較銅和銀的金屬活動性強弱,可選用上述藥品中的_________進行實驗(選填序號);
(2)上述有些藥品若敞口放置很容易變質(zhì)。試舉一例,說明變質(zhì)的原因________________;
(3)同學(xué)們欲探究標簽破損的藥品的成分。
《分析思考》根據(jù)藥品分類擺放的原則,該藥品可能是__________;
A.酸       B.堿      C.鹽       D.單質(zhì)
《作出猜想》①可能是NaOH溶液②可能是Na2CO3溶液③還可能是_____溶液(任寫一種)
《設(shè)計并實驗>
Ⅰ.小明用潔凈的玻璃棒蘸取樣品溶液滴至經(jīng)過潤濕的pH試紙上,測得pH=10,他判斷溶液顯堿性。對他的操作方法、測量結(jié)果及結(jié)論的評價,正確的是_______;
A.方法正確,結(jié)果正確,且結(jié)論正確  B.方法正確,結(jié)果正確,但結(jié)論錯誤
C.方法錯誤,結(jié)果偏小,但結(jié)論正確  D.方法錯誤,結(jié)果偏大,但結(jié)論正確
Ⅱ.根據(jù)以上結(jié)果,小明認為原試劑是氫氧化鈉溶液,但小俊認為小明的判斷錯誤。你贊同_______的觀點,理由是______________________________;
Ⅲ.小強選用圖中的試劑,在小明的實驗基礎(chǔ)上通過進一步的實驗確定它是Na2CO3溶液。請你補全小強的實驗報告。
選用試劑
實驗現(xiàn)象
結(jié)論
 
 
原試劑是Na2CO3溶液。
<反思與評價》小偉對小強的結(jié)論提出質(zhì)疑,認為該試劑還可能是_____________溶液。

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(3分)某大型洗衣店的廢水經(jīng)沉淀后直接排放到河流中,使入河口水中的藻類等浮游生物大量繁殖,水呈綠色。
(1)造成這種現(xiàn)象的原因可能是洗衣店排放的廢水中含較多的__________元素;
(2)資料顯示河水中的藻類的化學(xué)式為C xH yO110N16 P 。則該藻類中氮、氧元素的質(zhì)量比
為___________;
(3)已知該藻類相對分子質(zhì)量為3550,碳元素的質(zhì)量分數(shù)為35.8%。則式中x的近似值等于___________。

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