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问题 实验题

（7分）归纳是学习的重要方法，小红在复习盐酸的性质时，归纳出盐酸的五条化学性质（如图所示，连线表示相互反应）。

⑴为了验证性质①，小红将紫色石蕊试液滴加到盐酸溶液中，溶液变________________色；

⑵图中A所表示的物质类别是________________；

⑶盐酸的性质③决定了盐酸可用于清除铁锈（主要成分Fe2O3），该反应的化学方程式是________________________________；

⑷为了验证性质⑤，可选用的物质是________________（填一种即可）；

⑸镁和锌可以用来验证盐酸的性质②，小红要探究镁和锌与盐酸反应的快慢，需要控制不变（相同）的量是________________（填序号）；

A．两种金属的形状

B．盐酸的质量分数

C．反应容器的大小

D．温度

答案

⑴红   ⑵碱   ⑶Fe2O3+6HCl=2FeCl3+3H2O   ⑷Na2CO3（或AgNO3等等，合理即可）   ⑸ABD（先错不得分，选对2个得1分，全对得2分）

分析：（1）利用石蕊遇酸的变色情况分析即可．

（2）综合分析酸的化学性质可对A的类别进行判断．

（3）根据铁锈的成分结合与盐酸反应的产物对化学方程式书写即可．

（4）酸与盐的反应一定要符合复分解反应的发生条件．

（5）控制变量法就是创设相同的外部条件，并对所比较的量进行分析．

解：（1）石蕊遇酸性溶液会变红色，所以将紫色石蕊试液滴加到盐酸溶液中溶液变红．

（2）综合分析酸的化学性质可知：除去盐酸能与指示剂、金属氧化物、金属、盐反应外还能与碱发生中和反应．

（3）铁锈的主要成分是氧化铁，与盐酸反应时会生成氯化铁与水，依据化学方程式的书写要求书写即可．

（4）酸与盐的反应一定要符合复分解反应的发生条件，所以选择的盐与盐酸反应时一定会有水、气体或沉淀生成．

（5）控制变量法就是创设相同的外部条件，因此探究镁和锌与盐酸反应的快慢，需要控制不变的条件就是对反应速度可能有影响的因素，分析知四个因素中只有容器的大小对反应速度无影响．

故答案为：（1）红（2）碱（3）Fe2O3+6HCl=2FeCl3+3H2O（4）Na2CO3（或AgNO3等等，合理即可）（5）ABD

单项选择题 案例分析题

患者，男，60岁，双下肢无力7年。患者7年前无明显诱因出现双下肢疲乏，呈进行性加重，伴步态不稳，如"脚下踩棉花感"。时作颈项板滞，双上肢沉重、无力。查体：颈椎生理弧度变直，C棘旁压痛，双下肢肌张力增高，膝、踝反射亢进，Hoffmann（+），踝阵挛（+）。X光片示：颈椎退行性变。

该患者的初步诊断是（）

A.颈型颈椎病

B.脊髓型颈椎病

C.神经根型颈椎病

D.椎动脉型颈椎病

E.交感神经型颈椎病

F.混合型颈椎病
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阅读理解

.

Bill Gates was born on October 28th, 1955. He and his two sisters grew up in Seattle. Their father, William H. Gates II, was a Seattle lawyer. Mary Gates, their late mother, was a school teacher.

Gates attended public elementary school before moving on to the private Lakeside School in North Seattle. It was at Lakeside that Gates began his career in personal computer soft- ware, programming computers at age 13.

In 1973, Gates entered Harvard University as a freshman, where he lived down the hall from Steve Ballmer, who is now Microsoft's president. While at Harvard, Gates developed a version (版本) of the programming language BASIC for the first microcomputer---the MITS Astair. In his junior year, Gates dropped out of Harvard to devote his energies full-time to Microsoft, a company he had started in 1975 with his boyhood friend Paul Allen. Guided by a belief that the personal computer would be a valuable tool on every office desk-top and in every home, they began developing software for personal computers.

Gates' foresight has led to the success of Microsoft and the software industry. He plays an important role in the technical development of new products. Much of his time is devoted to meeting with customers and staying in touch with Microsoft employees around the world through e-mail.

In the dozen years since Microsoft went public, Gates has donated more than $ 800 million to charities (慈善机构), including $ 200 million to the Gates Library Foundation to help libraries in North America make use of new technologies and the Information Age.

50. Where did Bill Gates begin his career in personal computer software?

A. At public elementary school.                  B. At the private Lakeside School.

C. At Harvard University.                           D. At Microsoft Company.

51. Why did he drop out of Harvard?

A. To change school.                                 B. To spend all his energies to Microsoft.

C. To find a full-time job.                          D. To earn money.

52. How does Gates spend much of his time?

A. Meeting with people.                            B. Travelling around the world.

C. E-mailing some friends.  

D. Meeting with customers and e-mailing Microsoft employees.

53. What does the underlined word "donated" in the last paragraph mean?

A. gave.                B. earned.              C. made.               D. received.
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