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題目列表(包括答案和解析)

24、家庭廚房就是一個化學(xué)小世界,包含著許多化學(xué)知識,回答下列問題:
(1)大米、面粉的主要成分都是
淀粉
,食鹽的主要成分是
氯化鈉

(2)茶葉、肉松、膨化食品等常采用真空或充氣包裝,所充入的氣體可能是
氮?dú)狻⒍趸嫉?/div>.
(3)味精是烹制菜肴的調(diào)味品,味精的鮮味與溶液的酸堿度有關(guān),當(dāng)pH為6~7時鮮味最強(qiáng);味精的鮮味還與溫度有關(guān),其水溶液經(jīng)120℃以上長時間加熱,不僅鮮味消失,而且生成對人體有害的焦谷氨酸鈉.據(jù)此,下列認(rèn)識不正確的是
A
(填字母).
A.谷氨酸鈉在加熱條件下生成焦谷氨酸鈉是物理變化
B.菜燒熟起鍋后再放味精比炒菜過程中加入味精更有利于人體健康
C.加入味精時,應(yīng)避免在酸性或堿性較強(qiáng)的條件下使用
(4)若鍋里的油著火了,可采取的滅火措施是
蓋上鍋蓋
,其滅火的原理是
隔絕空氣
;
若要用蔗糖配制蔗糖水,為使蔗糖盡快溶解,說出兩種可采取的方法:①
攪拌
、②
升溫
;若要除去保溫瓶內(nèi)膽中的水垢,選用廚房中的
食醋
;
(5)家用煤爐中的蜂窩煤有12孔、14孔,甚至16孔等多個品種,你認(rèn)為孔道越
(填多、少)燃燒越充分.理由是
可燃物與氧氣接觸面積越大,燃燒越充分

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24、(1)指出下列屬于溶液的溶液中的溶質(zhì)和溶劑:
A、水銀;B、碘酒;C、氯化鈉注射液
溶質(zhì):
碘,氯化鈉
,溶劑:
酒精,水

(2)在餐桌上,當(dāng)我們發(fā)現(xiàn)某種湯很淡時,通常的做法是
加鹽
.這個過程中一定不變的是
A
,一定變大的是
BCD
.(請?zhí)钕铝羞x項中的字母)
A、水的質(zhì)量;B、湯的質(zhì)量;C、鹽的質(zhì)量;D、鹽的質(zhì)量分?jǐn)?shù)
(3)用400g溶質(zhì)質(zhì)量分?jǐn)?shù)為40%的氫氧化鈉溶液,配制成溶質(zhì)質(zhì)量分?jǐn)?shù)為16%的氫氧化鈉溶液,需要加入水的質(zhì)量是
600g

(4)如圖所示,充滿空氣的集氣瓶的瓶塞上同時插有一支盛有水的小試管和一支U形管.向小試管里加入一定量氫氧化鈉固體,則U形管內(nèi)液面變化情況是
左側(cè)液面下降,右側(cè)液面上升
;
原因是
氫氧化鈉溶于水放出熱量,使集氣瓶內(nèi)氣體溫度升高,壓強(qiáng)增大

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24、下表是部分元素的原子結(jié)構(gòu)示意圖、主要化合價等信息
請完成以下填空:
(1)與鋁原子的最外層電子數(shù)相同的原子是
B
(填元素符號).
(2)核電荷數(shù)為11元素形成的離子符號是
Na+
;其氧化物化學(xué)式是
Na2O

(3)原子序數(shù)為12和16的元素組成化合物的化學(xué)式
MgS

(4)請你總結(jié)出此表中的原子結(jié)構(gòu)與元素化合價或周期數(shù)的關(guān)系
原子的電子層數(shù)等于周期數(shù)(其他合理答案也給分)
(任寫一條).

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(1)24.5克H2SO4的物質(zhì)的量是______mol,
(2)11克CO2的物質(zhì)的量是______mol,
(3)2.5molNa2CO3的質(zhì)量是______g,
(4)1.5molH2O的質(zhì)量是______g;
(5)1.806×1023個CO2的質(zhì)量為______g,
(6)9.03×1023個H2SO4的質(zhì)量為______g,
(7)49g硫酸中含有______個氧原子,
(8)48g甲烷中含有______個氫原子;
(9)某混合物由NaCl、MgCl2、AlCl3組成,已知Na、Mg、Al三元素的質(zhì)量之比23:16:9,則NaCl、MgCl2和AlCl3物質(zhì)的量之比為______.

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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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