问题 实验题

(2012•湖州)如图装置可验证二氧化碳和氢氧化钠发生了化学反应:将等量的氢氧化钠溶液和蒸馏水分别加入两瓶等量二氧化碳气体中,用U型管连接.充分反应后放在水平桌面上可观察到U型管中液面出现高度差.

(1)室温下利用此装置,你还可以研究        

A.比较氧气和二氧化碳在水中的溶解能力

B.比较氯酸钾和氯化钠在水中的溶解能力

C.比较饱和氢氧化钠和氢氧化钙溶液吸收二氧化碳气体的能力

(2)进一步思考、迁移:有         变化的对比实验都可以用此装置进行探究.

答案

(1)A、C;(2)气压(或气体体积);

依据题干中关于验证二氧化碳和氢氧化钠发生了化学反应的实验现象可知,该装置适合验证两瓶中反应发生后出现气压差,从而导致U型管液面出现高度差的反应,据此对问题进行解析探讨即可;(1)A、氧气不易溶于水而二氧化碳能溶于水,将等量蒸馏水分别加入两瓶中的氧气和二氧化碳气体中,过一会儿后盛有二氧化碳的瓶中气压会小于成有氧气的瓶中气压,因此用U型管连接.上可观察到U型管中液面出现高度差;B、比较氯酸钾和氯化钠在水中的溶解能力的比较,采用该装置时不会导致两瓶出现气压差,因此不能采用该装置比较氯酸钾和氯化钠在水中的溶解能力;C、饱和氢氧化钠和氢氧化钙溶液吸收二氧化碳气体的能力不同,氢氧化钠吸收二氧化碳的能力较强,所以两瓶中会出现气压差,因此充分反应后放在水平桌面上可观察到U型管中液面出现高度差;(2)结合解析以及对(1)的解答可知该装置能够验证有气压变化的对比实验。

完形填空
完形填空(共20小题,每小题1.5分,满分30分)
Miss Green was watching TV. Suddenly the program stopped . "Now we broadcast an important notice from the  36 : At about nine this evening , an old woman of 79 ,named Mrs Humney , was 37 and killed by a robber (抢劫犯)wearing a green coat . Those who can supply any clue (线索)are requested to  38   to the police ." The  39 news made the lonely girl filled with  40  .She couldn't help looking around .But she didn't  41 that a man was already behind the door.
Suddenly the man  _42  before Miss Green . The girl didn't know what to __43 . " Just put your necklace on the table, then I’ll  44  whether I shall be safe to stay here for the night." said the robber. That made her even more terrified , but she tried to  45  herself.
Just then there came the whistle of a police car .Then  46  the door bell. The man said with a pistol(手枪) 47  the girl's back, " Don't  48  the door. Never let him in." But the girl got a(n)  49 . She asked the man outside the door , " Who is it ?" "I'm Bull. Is there  50  unusual here ?" "No, there isn't ." Immediately she added  51  ," only 52  and I are here." "Good night, " Bull replied in the same loud voice.
A few minutes later. The sound of the  53 died away. " It's well done, " the robber laughed. Almost at the same time the glass was  54  into pieces . The policemen  55  into the room and caught the robber.
"Miss Green , what you said made us take action right away, " said Bull, " for we know that you have no brother."
36. A. police        B. government          C. army                   D. prison
小题1:
A.hitB.stolenC.robbedD.cheated
小题2:
A.announceB.knowC.provideD.report
小题3:. A .terrible             B exciting                 C. strange                 D. funny
小题4: A. anger             B. fear                        C surprise                 D. sadness
小题5:
A.feelB.lookC.hearD.notice
小题6:
A.cameB.appearedC.walkedD.ran
小题7:.
A.sayB.makeC.doD.deal
小题8:
A.decideB.considerC.hopeD.doubt
小题9:
A.protectB.scareC.freeD.calm
小题10:
A.touchedB.hitC.rangD.struck
小题11:
A.againstB.inC.toD.over
小题12:
A.knockB.shutC.leanD.open
小题13:
A.beliefB.ideaC.helpD.voice
小题14:
A.anythingB.somethingC.anyoneD.someone
小题15:.
A.excitedB.anxiouslyC.loudlyD.bravely
小题16:.
A.my friendB.my neighbourC.the robberD.my brother
小题17:
A.policemanB.police carC.robberD.footsteps
小题18:
A.turnedB.broughtC.brokenD.changed
小题19:
A.slippedB.wentC.fellD.hurried
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