科学技术的发展使新物质不断出现,据报道,氮单质家族增加了几种新丁:如N60(结构

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问题:

科学技术的发展使新物质不断出现,据报道,氮单质家族增加了几种新丁:如N60(结构如图)、N4(结构同白磷)等,下列有关几种氮单质的说法中,正确的是

[ ]

A.N60是原子晶体,而N2、N4是分子晶体

B.N4、N60与N2相比更难与H2反应

C.28 g N60单质中含有的N-N键个数为3NA

D.等质量的N2、N4、N60分子数目比为30:15:2

考点:原子晶体无机分子的立体结构分子晶体
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完形填空(10分)

  What will our life be like in the future? Each family will have a  1 in the future. You can ask it to do everything  2  you. It will serve(服务) you  3 hours a day. The robot will  4 like a human. It can talk with you when you are  5 . You won’t know it is a human  6 a robot when you meet it on the street.

  People will have  7 time to work and more time to travel. The vehicles(交通工具) in the future will fly freely in the sky because every vehicle will have wings(翅膀) with it. They will  8 you to any place you want to visit. You can go to  9  when you have a travel if you feel tired. All vehicles will be  10  because of driving by robots.

小题1:A、rocket              B、robot               C、car

小题2:A、on                 B、about               C、for

小题3:A、eight              B、twenty              C、twenty-four

小题4:A、sound              B、live                C、look

小题5:A、happy              B、alone               C、comfortable

小题6:A、so                 B、and                 C、or

小题7:A、less               B、few                 C、more

小题8:A、make               B、take                C、let

小题9:A、school             B、work                C、sleep

小题10:A、safe              B、dangerous           C、unpleasant

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Which of the following signs can’t usually be found in a hospital?

A.

B.

C.

D.

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“异响”在英语中表达为()。

A、Buzz

B、Squeak

C、Rattle

D、Buzz,Squeak and Rattle

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耐火材料低抗高温作用而不熔化的性能称为()。

A.耐火度

B.抗渣性

C.热稳定性

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普通平键联接的主要失效形式是什么?

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