铝、铁、铜是人类广泛使用的三种金属,与我们生活息息相关。 (1)按人类开始使用这

题型:填空题

问题:

铝、铁、铜是人类广泛使用的三种金属,与我们生活息息相关。

(1)按人类开始使用这三种金属的先后排序为                    (用元素符号表示)

(2)在空气中       制品(填“铝”或“铁”)更耐腐蚀。

(3)人们大量使用的是合金而不是纯金属,这是因为合金具有更多优良性能,例如钢比纯铁硬度      (填“大”或“小”)。

(4)用铜制电线主要是利用铜具有良好的        性。

(5)铁制品锈蚀,实际上是铁跟空气中的             发生了化学反应。焊接铁制品时,通常先用稀盐酸除去其表面的铁锈,反应的化学方程式为                    。防止铁制栏杆锈蚀的一种方法是         

(6)用下列试剂验证这三种金属的活动性顺序,能达到目的的是         (填序号)

A.硫酸铝溶液        B.硫酸亚铁溶液        C.硫酸铜溶液

考点:金属的物理性质和用途一氧化碳还原氧化铜金属的化学性质金属的回收利用
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阅读理解。

     2012 is a good film. If I were you, I'd like to watch it. The words, "Everyone is equal,

and everyone has his chance of survival" , have been shocking to us.

     Things begin in 2009,as an Indian scientist has made a strange discovery:It seems that there are serious storms on the surface of the sun, which are having a great effect on earth. By 2010 the US President calls

a meeting with seven other famous world leaders at the G8 summit in Spain. He says the

world's top scientists have found out that the world will soon come to an end.

     Finally we reach the year 2012. By now, signs have been appeared. The west coast is with so-called "mini earthquakes",  and fissures (裂缝) often appear in the earth.  But people are going about their daily

lives as usual.  At this time, Jackson Curtis is going on a driving trip with his two young children in Yello

wstone National Park.

     Jackson and the kids arrive at Yellowstone to find that some parts of the park have been taken over for reasons they don't know.

     At the same time world leaders are planning to choose excellent people from all over the earth, and let

them get out of the cataclysm (灾难) by special built ships. Everyone else will be left to death.

     Jackson, of course, is not one of those chosen to be saved, but he tried his best to get on the ship with his family. The movie ends with a view of the Earth from space, showing a changed African continent.

1. What does the US president tell other famous world leaders at G8 summit in Spain?

A. The world will soon come to an end.

B. Serious storms are on the surface of the sun.

C. People on the earth can move to other planets.

D. The movie 20/2 is made up.

2. There are______ famous world leaders at the meeting that the US president calls.

A. 6

B. 7

C. 8

D. 70

3. Jackson Curtis is going to take his two children to______.

A. his home in Los Angeles

B. have a camping trip in Yellowstone National Park

C. watch the movie 2012

D. meet the cataclysm that brings an end to the world

4. If the person ______, he/she can get on specially built ships that can get out of the cataclysm.

A. is a scientist

B. is a president

C. is excellent

D. can make spaceship

5. If you watched the film, what would shock you'?

A. Jackson and the kids.

B. A global cataclysm that brings an end to the world.

C. People on the earth can move to other planets.

D. Everyone is equal, and everyone has his chance of survival.

题型:填空题

对设备进行加电测试的具体内容是什么?

题型:填空题

在微机的硬件设备中,有一种设备在程序设计中既可以当做输出设备,又可以当做输入设备,这种设备是( )。

A.绘图仪

B.扫描仪

C.手写笔

D.硬盘

题型:填空题

设3阶方阵A满足A2=0,则下列等式成立的是().

A.A=O

B.RA.=0

C.A3=O

D.RA.=3

题型:填空题

中国当前深化课程改革过程中所产生的种种教育热点问题(如“重点中学”存废之争、择校问题、民办教育与私立学校问题等)大都反映了()

A.人们对教育公平的渴望

B.人们对提高教育地位的渴望

C.人们对提高教育质量的渴望

D.人们对受教育权利的追求

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