问题 选择题

以下四个图象能正确反映对应变化关系的是(  )

A.①加热一定质量的高锰酸钾

B.②将铜片放入硝酸银溶液中

C.③木炭在密闭的容器内燃烧

D.④电解水生成两种气体

答案

A、热一定量的高锰酸钾制氧气时氧气的质量是不断增加的,当高锰酸钾完全反应后氧气的质量不再增加,不正确;

B、铜与硝酸银的反应生成银消耗铜,每反应一个铜原子则置换出两个银原子,固体质量会增加,直至反应结束,故正确;

C、木炭在密闭的容器内燃烧时二氧化碳的质量应该是增加的,不正确;

D、电解水时生成的氢气和氧气的体积比是2:1,图中是质量比,不正确.

故选B

阅读理解

Nowadays, computer games are becoming more and more popular in many cities and towns. A lot of small shops along busy streets have been made into small game houses in order to get more money. These places are always crowded with people, especially young boys.

In the computer game houses, people spend a lot of money competing (较量) with the machines. It's hard for one to win the computer, but one can make progress after trying again and again. People have a kind of gambling psychology(赌博心理) when they play computer games.The more they lose, the more they want to win. When class is over, the school boys run to the nearby computer game houses.Little by little! (渐渐地), they forget all about their lessons and fall far behind others. Some of them can get enough money from their parents. But some of them are not lucky enough to get the money. They begin to take away other students' money and become thieves.

小题1:Who always go to the computer game houses?

A.Young girls

B.Young children

C.Young students

D.Young boys.小题2:People made small shops into small game houses in order to ______.

A.make computer games more popular

B.get more money

C.help people to learn computer better

D.make people happy小题3:What must be brought to play games in the game homes?

A. Tickets.   B Paper    C. Cards.   D. Money.

小题4:What will happen to the boys if they keep going to the game houses?

A.They will win a lot of money.

B.They will make a lot of good friends there.

C.They will fail in their study and even break laws.

D.They will live a happy life in the future.小题5:What is the passage mainly about?

A.Game houses have a bad effect on young boys.

B.More and more small shops have been made into game houses.

C.Young boys spend a lot of money playing computer games.

D.People play games better after trying again and again.

单项选择题