问题 多选题

下列关于实验现象的描述,正确的是(  )

A.镁条在空气中燃烧,发出白色火焰,生成白色粉末

B.细铁丝在氧气里剧烈燃烧,火星四射,放出热量,生成黑色固体物质

C.加热试管里的氢氧化铜蓝色沉淀,蓝色沉淀没有变化

D.蜡烛在氧气里燃烧比在空气里燃烧得更旺,发出红光

答案

A、镁条在空气中燃烧,发出白光,生成白色固体粉末,发出白色火焰不对;故A不正确;

B、铁丝在氧气中点燃,剧烈燃烧,火星四射,生成一种黑色固体,放出大量的热;故B正确;

C、氢氧化铜加热分解生成黑色氧化铜和水;故C不正确;

D、蜡烛在氧气里燃烧比在空气里燃烧得更旺,发出白光,放出热量;故D正确.

故选BD.

阅读理解

阅读理解     

     Please help! I live in Germany with my wife and three kids. My parents live in the UK. I want my kids

to have as much contact with their grandparents as possible. The kids all use e-mail, Skype and SMS but my parents won't. I've bought them a laptop, paid for broadband, given them both mobile phones and a

digital camera, but they won't use them. My parents say they hate computers and new technology. What

can I do with these "technophobes"? 

                                                                                                                   Daniel, Buremburg, Germany

     Actually, the original technophobes were the Luddites, a group of cloth workers in 19th century Britain during the Industrial Revolution. The Luddite cloth workers, who traditionally made cloth by hand, were

worried that machines were going to take away their jobs and way of life. These machines could make

cloth much faster and cheaper than humans. In 1811 and 1812 the Luddites destroyed the machines that

they hated so much, but the British government supported the factory owners. Many Luddites were

arrested. Charlotte Bronte's novel Shirley will tell your parents all about it. 

                                                                                                                             Laura, Valencia, Spain

     Laura makes some interesting points, I think. Technophobes has been a common theme in science

fiction. Frankenstein, one of the first science fiction, is a warning of what could happen if humans began

to experiment with human life. 

                                                                                                                 Freda, Copenhagen, Denmark

     One thing you could try is to find hardware that is designed for older people to use. An example is the mobiles made by the US company, Jitterbug. Instead of icons and menus the Jitterbug phones ask users

simple "yes/no" questions and have larger keypads. The company realized that there are potentially 100

million older users in the US alone. 

                                                                                                                          Graham, Patras, Greece

1. The underlined part "the technophobes" in the passage refers to ______.

A. those who are ready to try new technology

B. those who are addicted to the Internet

C. those who refuse to use modern technology

D. those who are devoted to inventing new things

2. Which of the following is TRUE of the Luddites?

A. They called themselves the technophobes.

B. They got full support from their factory owners.

C. They preferred to keep their traditional working methods.

D. They were killed by the government.

3. Who has put forward a practical and useful suggestions?

A. Laura.

B. Freda.

C. Daniel.

D. Graham.

4. The passage is probably taken from _____.

A. a personal blog

B. a letter between friends

C. a personal diary

D. a speech on new technology

5. What can we infer from the passage?

A. Daniel would buy her parents a novel written by Shirley.

B. Charlotte Bronte wrote about technophobes in her novel Shirley.

C. Daniel would buy her parents cell phones with icons and menus.

D. Daniel worried about her children using e-mails.

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