问题 填空题

据报道,某商场开业庆典时,店外挂的氢气球因人群拥挤而被挤破,遇上点燃的香烟,引起爆炸,并引发邻近一串氢气球爆炸。迅速掠过的火苗烧了一些顾客的头发,并浅度灼伤20多人的皮肤。请简要回答:

(1)以上事实说明氢气具有什么化学性质                                     

(2)新的方案是:采用一种安全气体——氦气,作为大型升空气球的气体,由此推测应具有的性质是①                      ;②                         

答案

(1)易燃或可燃性,化学性质较活泼。

(2) ① 密度比空气小;  ② 化学性质稳定 。

题目分析:(1)氢气剧烈燃烧而爆炸的事实说明氢气具有什么化学性质易燃或可燃性,化学性质较活泼。

(2)新的方案是:采用一种安全气体——氦气,作为大型升空气球的气体,由此推测应具有的性质是①密度比空气小;;②化学性质稳定。

点评:氢气是密度最小的气体,易燃烧,化学性质活泼,是理想的能源;

氦气是稀有气体,密度小于空气,化学性质稳定。

填空题

Part 3


Questions 19-25


·Read the following article from the newspaper and answer questions 19-25.
·For questions 19-25, choose the correct answer A, B, CorD.
·Mark your answer on the Answer Sheet.

The Power of One


Can we overcome apathy Yes, but only if we have hope. One reason for hope lies in the extraordinary nature of human intellectual accomplishment. A hundred years ago, the idea of a 747, of a man on moon, of the Internet remained in the realm of science fiction. Yet we have seen those things and much, much more. So, now that we have finally faced up to the terrible damage we have inflicted on our environment, our ingenuity is working overtime to find technological solutions. But technology alone is not enough. We must engage with our hearts also. And it’s happening around the world.
Even companies once known only for profits and pollution are having a change of heart. Conoco, the energy company, worked with the Jane Goodall Institute (J.G.I.) in Congo to build a sanctuary for orphaned chimpanzees. Many other companies are working on clean forms of energy, organic farming methods, less wasteful irrigation and so on.
Another reason for hope is the resilience of nature—if it is given a helping hand. Fifteen years ago, the forests outside Gombe National Park in Tanzania had been virtually eliminated. More people lived there than the land could support. J.G.I. initiated the Lake Tanganyika Catchment Reforestation and Education Project (TACARE), a program active in 33 villages around the park. Today people improve their lives through environmentally sustainable projects, such as tree nurseries and wood lots. We provide health care, family-planning and education programs, especially for women. As their education increases, their family size tends to drop.
While pollution still plagues much of the world, progress is being made. This May in Sudbury, Ont., I saw new forests that were recolonizing hills destroyed by 100 years of nickel mining. The community raised the money and worked for months spreading lime and planting vegetation on the blackened rock. I released the first brook trout into a once poisoned creek there.
Animal species on the brink of extinction can be given a second chance through protection and captive breeding—-even if preserving a habitat conflicts with economic interests. A company in China planned to build a rapid-transit line right through the only major remaining breeding ground of the rare pheasant-tailed jacana. There was an outcry, but it was the only economically viable route. Environmentalists worked with the company to come up with a solution—moving the breeding ground. Water was diverted back into nearby wetlands that had been drained by farmers, and suitable vegetation was replanted. In 2000 five birds hatched in their new home, and when I visited there the next year, even more birds had moved to the site.
I derive the most hope from the energy and hard work of young people. Roots & Shoots, J.G.I.’s program for youth from preschool through university, is now active in 70 countries. The name is symbolic: roots and shoots together can break tip brick walls, just as citizens of Earth together can overcome our problems. The more than 4,000 groups of young people are cleaning creeks, restoring prairies and wetlands, planting trees, clearing trash, recycling and making their voices heard.
We have huge power, we have affluent societies, we are causing the most environmental damage. For we are the consumers, we do not have to buy products from companies with bad environmental policies. To help us, the Internet is linking small grassroots movements so that people who once felt they were on their own can contact others with the same concerns.

According to the passage, people can repair the damage by all the following means EXCEPT ______.

A.developing technology

B.planting trees and grassland

C.implementing family-planning programs

D.moving people out of the damaged areas

单项选择题