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问题 选择题

为除去实验室制得的CO2气体中的少量HCl气体，最好将混合气体通过(    )

A．烧碱溶液

B．饱和碳酸氢钠溶液

C．饱和碳酸钠溶液

D．饱和氯化钠溶液

答案

答案：B

题目分析：CO2和烧碱、碳酸钠都反应，A和C不正确。饱和食盐水吸收氯化氢的效果不如饱和碳酸氢钠好，因为碳酸氢钠能和氯化氢反应生成CO2，所以答案选B。

点评：该题是基础性试题的考查，试题注重能量的培养，该题难度不大。该题的关键是明确在解答物质分离提纯试题时,选择试剂和实验操作方法应遵循三个原则: 1.不能引入新的杂质（水除外），即分离提纯后的物质应是纯净物（或纯净的溶液），不能有其他物质混入其中；2.分离提纯后的物质状态不变；3.实验过程和操作方法简单易行，即选择分离提纯方法应遵循先物理后化学，先简单后复杂的原则。

完形填空
“You speak very good English”
The other day I heard an American say to a Chinese student of English. “You  1 very good English.” But the student answered, “ No, my English is very poor.” The foreigner was quite
  2 at the answer. Thinking he had not made himself  3 or the student had not heard him clearly, he said, “Yes, indeed, you speak it very well.” But the Chinese student still  4 saying  “No”.  5 the foreigner gave up and didn’t know what to say.
What’s wrong with the student’s answer? It is because he didn’t accept a compliment as the American people  6 . He should have said “Thank you” instead of “No”. He actually understood what the American had said. But he thought he should be modest. If someone says to a woman, “ You look  7 beautiful with the new clothes  8 .” she should be very happy and answer, “Thank you.” In our country we think  9 modest is a virtue and showing off is a bad behavior. But in the West, if you are modest and say, “ No,   10 I can’t do it well,” then the others will take it for granted (理所当然)that you  11 can not do it. If you often say,“No”, you will certainly be looked down upon by  12 . When  13 for a job, if one says something like “Yes, I can certainly do it” instead of “ Let me have a try on the job”, he or she can expect to get it. So in the West, one should always be confident.  14 self-confidence, he can’t go anywhere. Confidence is of great  15 to one in a country where competition is quite keen.(激烈)
小题1:
A．sayB．talkC．speakD．tell
小题2:
A．surprisingB．surprisedC．laughedD．laughing
小题3:
A．understoodB．understandC．to understandD．understanding
小题4:
A．keepB．keepingC．keepsD．kept
小题5:
A．At firstB．By the wayC．In the endD．First of all
小题6:
A．didB．doneC．to doD．do
小题7:
A．suchB．such aC．soD．so a
小题8:
A．forB．onC．inD．into
小题9:
A．beingB．beC．havingD．have
小题10:
A．I’m afraidB．I’m not sureC．I don’t mindD．I don’t know
小题11:
A．hardlyB．reallyC．badlyD．luckily
小题12:
A．anotherB．otherC．the otherD．others
小题13:
A．askingB．askC．provideD．providing
小题14:
A．WithB．WithoutC．byD．under
小题15:
A．importantlyB．unimportantC．importantD．importance
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单项选择题

因工作失误丢失重要空白凭证而造成的作废。重要空白凭证在领取、使用过程中，如果出现重要空白凭证遗失，应查明原因，追究当事人的责任，同时要登报声明作废，必要时到人民法院办理公示催告。是指（）

A、签发作废

B、改版作废

C、收回作废

D、交回作废

E、丢失作废
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