问题 选择题

(2011年山东济南,13题)在一硬质玻璃管中盛放着8g Fe2O3,通入CO气体高温加热一段时间,冷却后,测得玻璃管内的固体的质量减少了1.2g,则此时玻璃管内固体物质中铁元素的质量为下列的

A.6.8g

B.5.6g

C.2.8g

D.1.2g

答案

答案:B

由于变化前后铁元素的质量保持不变,都在试管内,所以可以根据氧化铁中的铁元素的质量确定最后固体中的铁元素的质量.氧化铁中的铁元素的质量分数为

56×2
56×2+16×3
×100%=70%,所以8g氧化铁中铁元素的质量为8g×70%=5.6g.而部分反应后的试管内物质,由于铁不会转化为气体逸出,所以铁元素的质量为5.6g.(本题很容易错误理解为使试管内的铁的质量,即单质铁的质量)

阅读理解

The word “sport” first meant something that people did in their free time. Later it often meant hunting wild animals and birds. About a hundred years ago the word was first used for organized games. This is the usual meaning of the word today. People spend a lot of their time playing football, basketball, tennis and many other sports. Such people play because they want to. A few people are paid for the sport they play. These people are called professional sportsmen. They may be sportsmen for only a few years, but during that time the best ones can earn a lot of money. For example, a professional footballer in England earns more than 30,000 dollars a year. The stars earn a lot more. International golf and tennis champions can make more than 500,000 dollars a year. Of course, only a few sportsmen can earn as much money as that.

Perhaps the most surprising thing about sportsmen and money is that the stars can earn more money from advertising than from sports. An advertisement for sports equipment does not simply say “Buy our things”. It says “Buy the same shirt and shoes as …”. Famous sportsmen can even advertise things like watches and food. They allow the companies to use their names or a photograph of them and they are paid for this. Sport is no longer just something for people’s spare time.

小题1:From the passage we can learnt that_______.

A.  people spend too much money on sports

the development of sport is slower than any other activity

most people enjoy sport because they can earn money

nowadays sport is not merely a pastime for people

小题2:Nowadays, the word “sport” means “________” .

A.what people do in their spare time

B.hunting wild animals and birds

C.organized games

D.something people are paid to do小题3:People play sports for ________.

A.fun

B.different

C.money

D.keeping fit小题4:What surprises people most is that ________.

A.the stars get more money from advertising

B.the word “sport” meant hunting animals

C.professional sportsmen are paid for what they do

D.only a few sportsmen can earn $500,000 a year

单项选择题