工业上根据氧气和氮气的______不同分离氧气的，首先将空气_______爱下问搜题

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问题填空题

工业上根据氧气和氮气的______不同分离氧气的，首先将空气______，除去______和______，然后在低温下，使空气______．通过控制温度______液态空气将沸点较低的液态氮先蒸发出来，余下的是沸点较高的液态氧了．

答案

在除去空气中的灰尘、二氧化碳和水蒸气后，液化空气，控制条件，氮气的沸点比氧气的沸点低，蒸发液态空气首先的到的是氮气，再把氮气和氧气分离，故填：沸点、除尘净化、二氧化碳、水蒸气、液化、蒸发．

完形填空

阅读下面短文，从短文后所给各题的四个选项中选出能填入空白处的最佳选项。
Many years ago, whites ruled South Africa. Apartheid（种族隔离制度）was the   16  of the land. One evening, two middle-aged blacks met in a “whites only” section of Johannesburg. One of them had a permit to work in the area, the other did not, which   17  he could be put behind bars（关押）for staying in this zone.   18  they saw a policeman coming towards them, and   19 .
“Run!” whispered the man with the permit to his friend, “I’ll   20 .” They started running and the policeman began chasing them, shouting “stop, stop”. Finally he caught the second man.
“Did you think you could outrun me!” he snarled. “Show me your   21 ！”
The man, playing for time, began reaching in his pocket and finally took out his permit. The policeman was surprised and realized that he had been   22 . The man without the permit was now too far away to be caught.
“When you had a permit why did you run!” he shouted   23 .
“Doctor’s   24 ,” said the man. “He has asked me to run a mile every evening.”
“Oh, yes? ” Sneered the policeman. “Then why was your friend   25 ?”
“His doctor has also ordered him to run,” said the man.
The policeman became   26  with anger. “You think you’re very   27 , don’t you?” he snarled. “But tell me, if you were running   28  for your health why didn’t you stop when you saw me running after you? And don’t tell me you didn’t see me chasing you. I know you did!”
“Of course I   29  you were running after me,” said the man.
“Then why didn’t you stop?” asked the policeman.
“It was   30 of me,” said the man, “but I thought you too had been ordered to run by your doctor.”

多项选择题

鸡尾酒的创作的要素是（）。

A.鸡尾酒创作的目的

B.鸡尾酒的创意

C.鸡尾酒创作的个性与特点

D.创造的联想