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绿色植物甲含有物质W，该物质为无色针状晶体，易溶于极性有机溶剂，难溶于水，且受热、受潮易分解。其提取流程为：植物甲→粉粹→加溶剂→振荡→收集提取液→活性炭处理→过滤去除活性炭→蒸馏(含回收溶剂)→重结晶→成品。回答下列问题：
(1)在提取物质W时，最好应选用的一种原料是_(填“高温烘干”“晾干”或“新鲜”)的植物甲，不宜选用其他两种的原因是_____。
(2)提取物质W时，振荡的作用是。
(3)活性炭具有很强的吸附能力，在提取过程中，用活性炭处理提取液的目的是_。
(4)现有丙酮(沸点56 ℃)、乙醇(沸点约78 ℃)两种溶剂，在提取物质W时，应选用丙酮作用提取剂，理由是______。
(5)该实验操作过程中应注意的事项是_(答出两点即可)。

【参考答案】

(1)晾干物质W受热、受潮易分解(2)使物质W完全溶于加溶剂(3)吸收有机溶剂和水分(4)其沸点相对较低，温度过高会导......

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阅读下列短文In the coming months, we are bringing together artists form all over the globe, to enjoy speaking Shakespeare’s plays

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In 1973, I was teaching elementary school.Each day, 27 kids 41 “The Thinking Laboratory.”That was the 42 students voted for after deciding that “Room 104” was too 43 .Freddy was an average 44 ,but not an average person. He had the rare balance of fun and compassion(同情).He would 45 the loudest over fun and be the saddest over anyone’s 46 .Before the school year 47 ,I gave the kids a special 48 , T-shirts with the words “Verbs Are Your 49 ” on them. I had advised the kids that while verbs(动词)may seem dull ,most of the 50 things they do throughout their lives will be verbs.Through the years, I’d run into former students who would provide 51 on old classmates. I learned that Freddy did several jobs after his 52 from high school and remained the same 53 person I met forty years before .Once, while working overnight at a store, he let a homeless man 54 in his truck . Another time , he 55 a friend money to buy a house .Just last year, I was 56 a workshop when someone knocked at the classroom door. A woman 57 the interruption and handed me an envelopE.I stopped teaching and 58 it up. Inside were the “Verbs” shirt and a 59 from Freddy’s mother. “Freddy passed away on Thanksgiving. He wanted you to have this.”I told the story to the class. As sad as it was, I couldn’t help smiling . Although Freddy was taken from us,we all 60 something from Freddy.41. A.built B.entered C.decorated D.ran42. A.name B.rule C.brand D.plan43. A.small B.dark C.strange D.dull44. A.scholar B.student C.citizen D.worker45. A.speak B.sing C.question D.laugh46. A.misfortune B.disbelief C.dishonesty D.mistake47. A.changed B.approached C.returned D.ended48.A.lesson B.gift C.report D.message49. A.friends B.Awards C.Masters D.Tasks50. A.simple B.unique C.fun D.clever51. A.assessments B.comments C.instructions D.updates52. A.graduation B.retirement C.separation D.resignation53. A.daring B.modest C.caring D.smart54. A.wait B.sleep C.study D.live55. A.paid B.charged C.lent D.owed56. A.observing B.preparing C.designing D.conducting57. A.regretted B.avoided C.excused D.ignored58. A.opened B.packed C.gave D.held59. A.picture B.bill C.note D.diary60. A.chose B.took C.expected D.borrowed

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