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问题 选择题

下列物质中与某些酸、碱、盐都能起反应的是（　　）

A．碳酸钙

B．碳酸钠

C．稀硫酸

D．氢氧化钠

答案

A、碳酸钙不溶于水，不能与碱或盐反应，故A不合题意；

C、稀硫酸是酸，酸都含有相同的H+，故不能反应，故C不合题意；

D、氢氧化钠属于碱，碱都含有相同的OH+，所以不能互相反应，故D不合题意；

B、而碳酸钠是盐，且可以溶于水，与酸反应会生成水和二氧化碳，与某些碱和盐会生成沉淀或水，符合题意．

故选B．

填空题

Part 2


Questions 9-18


Read the following passage and answer questions 9-18.
1. Most young people enjoy some forms of physical activity. It may be walking, cycling or swimming, or in winter, skating or skiing. It may be a game of some kind football, golf, or tennis. It may be mountaineering.
2. Those who have a passion for climbing high difficult mountains are often looked upon with astonishment. Why are men and women willing to suffer cold and hardship, and to take risks on high mountains This astonishment is caused probably by the difference between mountaineers and other forms of activity to which men give their leisure.
3. Mountaineering is a sport and not a game. There are no man-made rules, as there are for such games as golf and football. There are, of course, rules of a different kind which would be dangerous to ignore, but it is this freedom from man-made rules that makes mountaineering attractive to many people. Those who climb mountains are free to use their own methods.
4. If we compare mountaineering with other more familiar sports, we might think that one big difference is that mountaineering is not a "team game". We should be mistaken in this. There are, it is true, no "matches" between "team" of climbers, but when climbers on rock face linked by a rope on which their lives may depend, there is obviously teamwork.
5. The mountain climber knows that he may have fight forces that are per and more powerful than man. He has to fight to against the forces of nature. His sport requires high mental and physical qualities. A mountain climber continues to improve in skill year after year. A skier is probably past his best by the age of thirty, and most international tennis champions are in their early twenties. But it is not unusual for a man of fifty or sixty to climb the highest mountains in the Alps. They may take more time than young man, but they probably climb with more skill and less waste of effort, and they certainly experience equal enjoyment.

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.
  • A. Mountaineering is different from golf and football.
  • B. Mountaineering is treated as a team sport.
  • C. The requirements needed for climbers.
  • D. Many young people enjoy some forms of physical activity.
  • E. A mountain climber’s skill is not limited by his age.
  • F. The reason why people enjoy climbing mountains.
  • G. Mountaineering is a sport rather than a gam

Paragraph 5: ______
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选择题

The space suits can be adjusted so that the team can reproduce different levels of gravity as if they________in space.

A．are　

B．has been

C．were　

D．had been
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