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问题 选择题

下列叙述中，甲金属一定比乙金属活泼性强的是（　　）

A．甲原子电子层数比乙原子的电子层数多

B．在甲乙两种金属和盐酸构成的原电池中，甲作正极，乙作负极

C．1mol甲和乙分别与足量的盐酸反应，产生H2的量：甲＞乙

D．常温时，甲能从水中置换出氢，而乙不能

答案

A、如金属不位于同一主族，则不能根据电子层数的多少来判断金属的活泼性强弱，故A错误；

B、在甲乙两种金属和盐酸构成的原电池中，甲作正极，乙作负极，说明乙活泼，故B错误；

C、产生氢气的多少取决于金属失去电子数的多少，与金属的活泼性无关，故C错误；

D、金属的活泼性越强，越易与水反应，故D正确．

故选D．

阅读理解

Bill Gates was born on October 28, 1955. He grew up in Seattle, Washington in the US. He was a very clever boy. His favorite subjects at school were science and math. When he was 13, he started to play with computers. At that time, computers were large machines（机器）. Once he was very interested in a very old computer. He and some of his friends spent lots of time doing unusual things with it. In the end, they worked out a software program（软件程序） with the old machine. Bill sold it for $4,200 when he was only 17.

In 1973, Bill went to Harvard University(哈佛大学). In his third school year, he left Harvard to work for a company called Microsoft（微软）. Bill began his company（公司） in 1975 with his friend Paul Allen. They thought the computer would come into every office and every home soon. So they began developing(发展) the software for personal computers. They improved(改进) the software to make it easier for people to use computers.

小题1:Bill Gates grew up in _______.

A．Canada

B．Australia

C．America

D．Germany小题2:What subjects did Bill like best at school?

A．Science and math

B．Languages and art

C．Math and languages

D．Music and P.E小题3:Bill’s company worked hard at _______.

A．making large machines

B．playing computer games

C．mending old machines

D．developing software小题4:Bill started to play with computers ______.

A．in 1955

B．in 1968

C．in 1973

D．in 1975小题5:The underlined word “personal” means _______.

A．个人的

B．公众的

C．大型的

D．昂贵的
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选择题

物体做匀速直线运动时，它（　　）

A．受到的合力一定为零

B．具有的势能一定不变

C．具有的机械能一定不变

D．具有的内能一定不变
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