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问题 实验题

实验室中用含少量CO2杂质的CO来还原铁的氧化物FexOy并证明CO能够还原FexOy，且本身被氧化为CO2，实验所提供的各种仪器和药品如下：

(1)实验时，上述仪器装置的正确连接顺序是(填写各接口的代号)。混合气体―→________，________接(F)，(E)接________，________接________，________接________。

(2)在装置乙中发生反应的化学方程式是_______________________。

(3)在装置甲中发生反应的化学方程式是______________。

(4)丙装置中澄清石灰水的作用是_______________。

(5)经定量测定，0.4 g FexOy与CO反应生成的气体通入过量的澄清石灰水中，生成0.75 g白色沉淀，则FexOy中x值是________，y值是________。

(6)实验过程中，能说明CO能够还原FexOy的实验现象是___________。能够说明CO被氧化成CO2的实验现象是____________。

答案

(1)D　C　A　B　H　G　I

(2)2NaOH＋CO2=Na2CO3＋H2O

(3)FexOy＋yCOxFe＋yCO2

(4)检验CO2是否除净

(5)2　3

(6)固体粉末从红色变黑色　丁中澄清石灰水变浑浊

据实验目的，分析每个装置的作用，然后连接；x、y值的计算依据C守恒关系CO～CO2～CaCO3

n(CaCO3)＝n(CO)＝0.75/100＝7.5×10－3mol

FexOy中氧的质量为44 g·mol－1×7.5×10－3mol－28 g·mol－1×7.5×10－3mol＝0.12 g

n(Fe)＝＝0.005 mol，

n(O)＝0.12/16＝0.007 5 mol，

x/y＝2/3

读图填空题

在画生物图时，图中结构名称尽量注在图的             侧。
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阅读理解

三、阅读（共两节，满分40分）

第一节：阅读下面短文，从每题所给的A、B、C、D四个选项中，选出最佳选项，并把答案写在答题卷上。（共15小题，每小题2分，满分30分）

A

Some people have the feeling that nothing can be done about their poor reading ability. They feel hopeless about it. Can you learn to read better, or must you agree that nothing can be done about it?

To be sure, people are different. You cannot expect to do everything as well as certain other people

do. If all the students in a class tried out for basketball, some would be very good players; others would be very poor; and many would be in between. But even the very poor players can become much better players if they are guided in the right way, and with plenty of practice. It is the same with reading. Some seem to enjoy reading and to read well without any special help. Others find reading a slow and tiring job. In between, there are all degrees of reading ability.

Many experiments have shown that just about every poor reader can improve his reading ability. In these experiments, the poor readers were given tests of reading ability. After some of the causes of their reading were discovered, they were given special instruction and practice in reading. After a few months, another test of the same kind was given. In nearly all cases, these people had raised their reading scores.

41.   With the example of basketball players, the author shows ________.

A. why certain people are poor readers        B. that there are differences in people’s abilities

C. why some people are good basketball players

D. that good basketball players can be good readers

42.   To improve their reading ability, people should ________.

A. work long and hard                               B. take different forms of tests

C. have special help and practice                 D. try different reading materials

43.   The experiments mentioned in the text show that ________.

A. good readers seem to enjoy reading        

B. almost all poor readers can make progress

C. causes of poor reading were difficult to find out

D. tests help people improve their reading ability

44.   What does the underlined sentence “many would be in between” mean?

A. It means that many are the best basket players.

B. It means that many are the worst basket players.

C. It means that many are standing in the middle of the line.

D. It means that there are several levels of players in many students.

45.   What’s the purpose of the author’s writing this passage?

A. To encourage people to improve their reading ability.

B. To suggest that readers should do practice only in reading.

C. To tell us that readers can’t improve their reading ability without special help.

D. To tell us that to be a good reader, one should be guided in the right way.
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