题干

O、Si、Al是地壳中含量最多的三种元素,Na、Mg、Cl是海水中的重要元素.下列说法正确的是(   )

A:普通玻璃、水泥成分中都含有O、Si、Al三种元素

B:从海水中制备Na、Mg、Al三种元素单质的反应都是氧化还原反应

C:电解熔融状态的SiO2、Al2O3可以制得Si、Al,且都有氧气生成

D:加热蒸干NaCl、MgCl2溶液时可以得到晶体NaCl、MgCl2

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答案(点此获取答案解析)

B

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【20世纪战争与和平】阅读材料,回答问题

材料:英国虽然率先完成了第一次的工业革命,但直至20世纪初,英国教育一直“重文轻理”。媒体也把从事科学工作的人称为“科学人”(ScientificMen)而不是“科学家”(Scientist)。英国学习科学的学生数量也远不及德国,曼彻斯特等英国科研重镇的主要工作是由聘请的德国学者负责。1913年的调查显示,英国大学聘用的科学人才工资还不如教堂里的工作人员。由于对于科研人员都没有什么特殊的待遇,英国适龄科研人员大量应征入伍,研究工作人手短缺。开战后英国立刻失去了需要从德国进口的各种原材料时,英国人才发现他们科研实力不足带来的严重后果:军装染料、战备药品、实验仪器乃至枪械的瞄准镜都无法完全自行生产。而战场上——毒气、机关枪、手榴弹、火焰喷射器、潜艇、航空母舰等新式装备完全颠覆了战争的模式。

    工业的严重落后和军队的巨大伤亡让英国政府迅速认识到了应用科学研究与新技术研发在战场上的重大作用。1916年英国的大学教育制度进行改革废除希腊语考试,引入博士学位制度。1918年英国教育部设立科学与工业研究部,为大学科研提供资助……这些变化,令科研不再是只有富裕的上等阶层才能从事的带有隐秘色彩的私人活动,渐渐成为一项普通人也可以从事的职业。

——卡德韦尔《科学与一战》

同类题5

任务型阅读

    The Winner's Guide to Success

    How do successful people think? What helps them to make success? To find out the answers, an American scholar recently visited some of the most successful people in America.____.

    Be responsible for yourself

    Sometimes you may want to blame others for your failure to get ahead. In fact, when you say someone or something outside of yourself is stopping you from making success, you're giving away your own power. You're saying, “You have more control over my life than I do.”

    Live life “on purpose”

    Almost all successful people live life “on purpose”____.When you live your life on purpose, you'll try your best to do your job or study as well as you can. You love what you do and you can find pleasure in what you do.

Write a plan

    It is very difficult trying to get what you want without a good plan. It is just like trying to drive through strange roads to a city far away.____ Without this “map”, you may waste your time, money and also your energy; while with the “map” you'll enjoy the “trip” and get what you want in the shortest possible time.

    Be willing to pay the price

    Nothing great is easy to get. So you must be ready to work hard-even harder than you have ever done. If you are not willing to pay the price, you won't get anything valuable.

    ____It seems to us that everyone knows this. But it is easier said than done. When you are doing something, you must tell yourself again and again: Giving up is worse than failure because failure can be the mother of success, but giving up means the death of hope.

    Don't delay

    Once an American writer was writing a novel. He could not have a good ending for his book until one night when he had a very good idea. He was so excited that he made a phone call to one of his best friends. “I've got a perfect idea,” he said, “I'll put it down later and show it to you.” But he never did, because he died that night. His book was left without a perfect ending____. Never delay at all.

A. Some people achieve success much later in life because they fail to realize earlier the importance of hard work

B. So remember, do what you can right away

C. Never give up

D. A good plan is like a map to you

E. Here are some keys to success that they give

F. They are doing what they believe they should and want to do

G. Make a decision