【多选题】【消耗次数:1】
常用溶剂中不能与水完全混溶的溶剂是
乙醇
丙酮
乙醚
正丁醇
氯仿
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相关题目
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【单选题】 在同一溶剂中,易溶气体的m值较小。( )
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【多选题】 精制皂苷时,先将粗皂苷溶于甲醇或乙醇,然后加何溶剂可使皂苷析出
①  乙醚
② 
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【多选题】 下列浸提方法中,哪些方法适合以乙醇为溶剂进行提取
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①  正确
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【判断题】 问:正丁醇(CH3CH2CH2CH2OH)的沸点(117℃)比它的同分异构体乙醚(CH3CH2OCH2CH3)的沸点(34.5℃)高得多,但两者在水中的溶解度均为8g/100g水,试解释之。 解:正丁醇分子之间可以形成分子间氢键,而乙醚分子之间不能形成氢键,所以正丁醇的的沸点远高于乙醚。但二者均可水分子形成氢键,所以它们在水中都有一定的溶解度(8g/100g水)。 评:这个解释合情合理!
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随机题目
【单选题】 2. When we speak to people, we should be ___.
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③  as politely as possible
④  as politely as possibly
【单选题】 7. This pencil is ____than that one.
①  longest
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【单选题】 16. The jacket was so ____ that he decided to buy it.
①  much
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【单选题】 17. Our classroom is ____ larger than theirs.
①  more
②  quite
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【单选题】 19. Your room is ____ mine.
①  twice as large
②  twice the size of
③  bigger twice than
④  as twice large as
【单选题】 4. I think the story is not so ____as that one.
①  interesting
②  interested
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④  most interesting
【单选题】 3.This book is ____that one, but ____than that one.
①  as difficult as; expensive
②  as more difficult as; more expensive
③  as difficult as; more expensive
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【单选题】 8. My mother is no ____young.
①  shorter
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【单选题】 20. Your room is ____ than mine.
①  three time big
②  three times big
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【单选题】 18. The earth is about ____ as the moon.
①  as fifty time big
②  fifty times as big
③  as big fifty times
④  fifty as times big