试题与答案

已知潜水员在岸上和海底吸入空气的密度分别为1.3kg/m3和2.1kg/m3,空

题型:计算题

题目:

已知潜水员在岸上和海底吸入空气的密度分别为1.3kg/m3和2.1kg/m3,空气的摩尔质量为0.029kg/mol,阿伏伽德罗常数NA=6.02×1023mol-1。若潜水员呼吸一次吸入2L空气,试估算潜水员在海底比在岸上每呼吸一次多吸入空气的分子数。(结果保留一位有效数字)

答案:

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题型:综合

城市是社会经济发展最活跃的地区,读图回答。(10分)

(1)甲图中1950年至2000年,该地区城市发展变化的特征直接表现                          。(4分)

(2)乙图中的①②两线中,最有可能反映G城人口变化特点的是    线,20世纪80年代以来,G城的人口变化特点是          ,其主要原因是社会、经济、环境问题突出,表现在                              等。(6分)

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题型:阅读理解

阅读理解。

     Apparently, we are safe neither at home nor in the business office. We use water in both places, but the

research shows that chemicals added to our local water supply to kill harmful bacteria can have unwanted

side effects. These chemicals can cause potential harm through drinking and in seemingly harmless activities

as cleaning one's house. They are released (set free) from water by daily actions like water running out of tap,

spraying from garden pipes, or splashing in dishwashers and washing machines. As the water is moving, these

chemicals are released into the air and then breathed in. Once inside our bodies, they start to affect our health.

     Does this mean we should stop bathing? No, say the scientists, but we should put all pollution into

perspective. Activities at home such as the burning of coal, cooking oil, or even candles release carbon

monoxide and particulates such as cigarette ashes which have been proven as harmful to health as working or

living near heavy traffic. New rugs, bedding, and even clothing give off that "new smell," which is a sure sign

of chemicals. In the office, newly applied paint, newly purchased telephones and other telecommunications

equipment, and computers release polluting chemicals, too. As offices and homes often have inadequate

ventilation (通风), these chemicals can build up to become health problems. Their poisonous effects are only

now being slowly recognized.

     These facts suggest that, at a minimum, proper airing of newly purchased goods with an obvious chemical

smell is a wise warning. Home and office windows should be opened during good weather. Evenone's car

needs to be ventilated as well while in the garage.

     We need further research to understand better other potential health dangers, too. For example, the effects

of overcrowding of schools (carbon dioxide build-up), the factory work environment (an endless list of

potentially dangerous substances), and even home heating and cooling (the air conditioner may be our enemies,

not our friends) have only recently started to come to light. Until we understand the effects of our new

technological environment better, we can only hope that "there is no place like home."

1. What is the main idea of the first paragraph?[ ]

A. The air we breathe in is harmful.

B. The water in everyday use is unsafe.

C. Chemicals are added to the drinking water.

D. Chemicals are released in the running water.

2. In Paragraph 2, the underlined sentence means that _____. [ ]

A. bathing should be done with caution

B. homes and offices should be aired often

C. any pollution should be taken into consideration

D. we should prevent any pollution from doing harm to us

3. What is the purpose of the passage?[ ]

A. To call on us to guard our water.

B. To show us that no place is like home.

C. To make us aware of the pollution around us.

D. To argue that neither homes nor offices are safe.

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