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(5分)化学与人类的生活和社会发展有密切的关系，试用你所学的化学知识回答下列问题：

(1)国务院曾于两年前就发出“限塑令”，以限制生产和使用塑料购物袋。

①塑料属于________(填“天然”或“合成”)材料；

②聚乙烯塑料完全燃烧产生二氧化碳和水，由此可知聚乙烯塑料中一定含有____________元素；

③从环境或能源角度，谈一点限制生产和使用塑料购物袋的意义_________________。

(2)粮食是人类主要食物来源，粮食问题已成为被世界关注的热点之一。

①粮食的主要成分是淀粉，它属于人体必需的有机物中的________________________；

②维生素也是人体所必需的有机物之一，它主要来源于食品中的______________。

答案

(1) ①合成　②碳和氢　③抑制白色污染(或节约石油资源或节约能源)　

(2)①糖类　②水果和蔬菜

（1）①塑料属于有机合成材料；

②聚乙烯塑料完全燃烧产生二氧化碳和水，根据质量守恒定律的元素守恒可知聚乙烯塑料中一定含有碳、氢元素，而由于燃烧是和氧气进行的反应，所以是否含有氧元素不能下结论．

③塑料购物袋的使用是导致白色污染的主要原因之一，所以从环境或能源角度分析限塑令能抑制白色污染（或节约石油资源或节约能源）的产生；

（2）①粮食的主要成分是淀粉，它属于人体必需的有机物中的糖类；

②维生素也是人体所必需的有机物之一，它主要来源于食品中的水果和蔬菜．

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对于截面形状复杂的钢筋混凝土受压构件，为避免产生向外的拉力，而使折角处混凝土保护层崩脱，不应采用______箍筋。
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Part 2


Questions 9-18


·Read the following passage and answer questions 9-18.
1. When Christopher Columbus landed on America’s shores, he encountered copper-shinned people whom he promptly called "Indians". Current estimates indicate that there were over a million Indians inhabiting North American then. There are approximately 800,000 Indians today, of whom about 250, 000 live on reservations.
2. The early settlers had an amicable relationship with Indians, who shared their knowledge about hunting, fishing, and farming with their uninvited guests. The stereotyped stealthy, wicked Indian of western movies are created by different faithless white man; the Indian was born friendly.
3. Disgust developed between the Indians and the settlers, whose encroachment on Indian lands provoked an era of turbulence. As early as 1745, Indian tribes joined together to drive the French off their land. The French and Indian war did not end until 1763. The Indian had succeeded in destroying most of the settlements. The British, superficially submissive to the Indiana, promised that further migrations west would not extend beyond a specified boundary.
4. Vacated from their lands or, worse still, frankly giving their property to the whites for few baubles, Indians were ruthlessly pushed west. The battle in 1876 at Little Horn river in Montana, in which setting Bull and the Sioux tribes massacred General Custer’s cavalry, caused the whites intensify their campaign against the Redman. The battle at Wound Knee, South Dakota, in 1890 put an end to the last vestige of hope for amity between Indians and whites.
5. Although the Bureau of lndian affairs has operated since 1842, presumably for the purpose of guarding Indians "interests", Indian on reservations lead notoriously deprived lives. In recent times Indians have taken a militant stand and appealed to the courts and the American people to improve their substandard living conditions.

Questions 9-13


·For questions 9-13, choose the best title for each paragraph from below.
·For each numberedparagraph (1-5), mark one letter (A-G) on the Answer Sheet.
·Do not mark any letter twice.
9. Paragraph 1: ______
  • A. Indians, once the master of America, now live in their
    reservation.
    10. Paragraph 2: ______
  • B. Indians were pushed away.
    11. Paragraph 3: ______
  • C. The wars between Indian and the settlers.
    12. Paragraph 4: ______
  • D. Indians arestill fighting for the improvement of their lives.
    13. Paragraph 5: ______
  • E. The relationship between Indians and the early settlers.
  • F. Indians were ferocious savages.
  • G. Indian’s struggle for their own possessions.
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