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(2011?張掖)雞蛋殼的主要成分是碳酸鈣.某興趣小組為了測定雞蛋殼中CaCO3的含量,現(xiàn)取15g雞蛋殼,搗碎,放在燒杯中,然后向其中加入80g某濃度的稀鹽酸,使之充分反應(雞蛋殼中除CaCO3外的其他成分都不溶于水,且不與稀鹽酸反應),測得燒杯中的反應剩余物的質(zhì)量(m)與反應時間(t)的關系如圖所示(忽略水蒸氣的揮發(fā)),其中當反應進行到B點時,所用鹽酸剛好完全反應.試計算(計算結(jié)果保留1位小數(shù)):

(1)產(chǎn)生CO2的質(zhì)量為_________g;
(2)該雞蛋殼中CaCO3的質(zhì)量分數(shù).
(3)反應后濾去不溶物所得溶液中溶質(zhì)的質(zhì)量分數(shù).

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空氣的成分中,約占總體積78%的氣體是(   )
A.氮氣B.氧氣C.二氧化碳D.稀有氣體

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下列物質(zhì)中,屬于氧化物的是(  )
A.H2OB.NaClC.NaOHD.C2H5OH

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最清潔的燃料是(  )
A.煤B.汽油C.氫氣D.一氧化碳

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下列物質(zhì)與水混合,能形成溶液的是(  )
A.沙子B.蔗糖C.氯化銀D.植物油

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NaOH溶液的pH(  )
A.等于0B.小于7C.等于7D.大于7

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科目: 來源: 題型:閱讀理解


It’s not easy to be an astronaut’s son.Everybody expects you to be special or perfect.I
often wonder how my father ever had a son like me.I mean he’s so special and so good at
everything he does.Even in middle school he was class president and captain of the football
team.
Well,to be honest,I often dream about being some kind of hero or doing something
special—like saving a child from a burning building or discovering a new star.I was daydreaming at school one morning when my teacher said there would be a Father’s Day writing competition for the whole sch001.“I hope we have a winner right here in my class.”
When I got home,I started to think about what to write.My father is an astronaut.N0,I
wouldn’t start like that.That was the way others saw him.How did I see my father? Hmm.
I saw him sitting with me in the dark when I had a terrible dream.I remembered how he
hugged me for hours when my dog Spotty was killed by a car.Yes,these were the things I
was going to write.To me,he wasn’t just a world—famous astronaut.He was my dad.
My parents and l went to school Thursday night.There were so many people in the big
hall! My dad looked at me,and I shrugged(聳肩).
The third prize was announced and it was not me.1 was relieved(釋然)and disappointed at the same time.The second prize was announced.It was me.
1 went up to the stage and read what I had written,“My father’s son”.When I finished,the people stood up and cheered.I saw my father blowing his nose.Tears were running down my mother's face.Dad cleared his throat and put his hand on my shoulder.“Son,this
is the proudest moment of my life.’’
It was the proudest moment of my life,too.Maybe I’ll never be a great hero or win a
Nobel Prize,but it was enough just to be my father’s son.
根據(jù)材料內(nèi)容選擇最佳答案,并將其標號填入題前括號內(nèi)。
【小題1】The writer felt it       to be the son of a famous person.
A.1uckyB.naturalC.hardD.pleasant
【小題2】In order to_       the writer would like to save a child from a burning building.
A.become astronautB.become a great hero
C.be made school team captainD.be made class president
【小題3】What did the boy probably write in his composition?
A.A lot of special things he had done.
B.The story of his father as an astronaut.
C.The unforgettable time he spent with his father.
D.The experiences his father had in middle school.
【小題4】The writer felt proud when he          
A.got a prize in a writing competitionB.won a Nobel Prize
C.saved a child from a burning buildingD.discovered a new star
【小題5】What is the best title for the passage?
A.My daydreamB.My father’s son
C.My famous fatherD.My happy family

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