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4、有机物中的乙烯(C2H4)、丙烯(C3H6)、丁烯(C4H8)等,它们的组成和结构都很相似,这类有机物被称作为烯烃。据此推断碳原子数为n的烯烃的化学式为   (   )

A、CnH2n    B、CnH2n+2     C、CnH2n-2    D、CnHn

 [解析]烯烃的化学式中氢原子的个数为碳原子个数的2倍

[答案]A

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3、家庭常用物质中属于无机物的是(  )                    

 A.葡萄糖      B.淀粉        C.水        D.蔗糖

[解析] 水中不含碳元素,属于无机物。

[答案]C

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2、玻璃是  (  )

A.纯净物  B.混合物  C.单质  D.化合物

 [解析]玻璃是一种硫酸盐材料,由石英砂(主要成分为SiO2)、纯碱、石灰石经过复杂的物理变化和化学变化反应而成,所得主要成分有Na2SiO3、CaSiO3 、SiO2。因此是混合物。

[答案]B

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1、有机高分子合成材料的出现是材料发展史上的一次重大突破。下列物质中存在有机高分子合成材料的是(  )

A汽车轮胎    B不锈钢     C棉花    D木头

 [解析]不锈钢不属于高分子材料;棉花、木头属于有机高分子天然材料;汽车轮胎属于有机高分子合成材料。

[答案]A

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第三节  书面表达(满分30分)

最近,很多中学生都纷纷开起了自己的博客。一方面,博客可以作为展示自己的窗口,可以释放学习的压力,因此已经被越来越多的中学生所接受。但是,另一方面,很多家长和老师都认为管理个人博客要花相当多的时间和精力,会耽误学习。

请对这一现象进行简要介绍,并发表自己的看法。  

注意:1.词数:l00左右,开头已给出,不计入总词数;

2.参考词汇:开博客open one’s blog。

Nowadays, it is a common phenomenon that more and more high school students open their own blogs on the Internet.                       

                                       

                                        

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第二节  短文改错(共10小题,每小题1.5分,满分l5分)

此题要求改正所给短文中的错误。对标有题号的每一行做出判断:如无错误,在该行右边的横线上画一个勾(√);如有错误(每行只有一个错误),则按下列情况改正:

此行多一词:把多余的词用斜线(\)划掉,在该行右边横线上写上该词,并也用斜线划掉。 

此行缺一词:在缺词处加一个漏字符号(∧),在该行右边横线上写出该加的词。

此行错一词:在错的词下面画一横线,在该行右边横线上写出改正后的词。

“Practice makes perfect” was an old saying. It tells us that it       76.  

does not any matter if we are slow at doing something. As        77.  

long as we keep on trying and practice, we’ll do a good job       78.  

in the end. The saying is especial useful in English study.        79.  

Since a student is poor at speaking, he should grasp every        80.  

chance to open mouth and speak English. His oral English        81.  

may be excellent one day due to his hard works. Not only is       82.  

the saying useful in English study, it is also helpful in our        83.  

daily life. To an extent, it is no short cut in doing everything       84.  

since key to success lies in “Practice makes perfect”.         85.  

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第一节  单词拼写(共10小题;每小题1分,满分10分)

根据下列句子及所给汉语注释,在横线上写出空缺处各单词的正确形式(每空只写一词)。

66. He turned quickly away, more in     (悲痛)than in anger.

67. Greece is a      (欧洲)country with a very long history.

68. Can you tell the     (相似之处)and the differences as well?

69. This is an    (难忘的) holiday.

70. Nothing can change our minds. We’re   (决心)to fight for our own rights.

71. Last year , China’s tourism earned 17.8 billon US dollars,    (排名)fifth in the world.

72. It is bad for his health to play computer games    the night.(整夜)

73. The army was well-trained and well-armed, and had little difficulty    (战胜) their enemy.

74.    (致力于)to his research, he had little time to spend together with his family.

75. Vegetables   (含有) a lot of vitamins.

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