问题 问答题

通过一段时间的化学学习,我们认识了一些物质的性质和用途.

(1)请选取相应物质的序号填空:

A.二氧化硫       B.酒精       C.活性炭       D.高锰酸钾

①______是实验室最常用的燃料;

②______是一种暗紫色的固体;

③______是一种空气中常见的气体污染物;

④______可用于吸附冰箱内的异味.

(2)国家已明令禁止灌装手持氢气球,是因为氢气______,该性质属于氢气的______性质(选填“物理”或“化学”);常用氦气取代氢气灌装气球,是因为氦气______.

答案

(1)①酒精具有可燃性,是实验室最常用的燃料,

②高锰酸钾是一种暗紫色的固体.

③二氧化硫是一种空气中常见的气体污染物.

④活性炭具有吸附性,能吸附异味和色素,可用于吸附冰箱内的异味.

(2)氢气具有可燃性,与空气混合遇明火可能爆炸,应明令禁止灌装手持氢气球;该性质属于氢气的化学性质.氦气密度比空气小,属于稀有气体,化学性质很不活泼,常用氦气取代氢气灌装气球.

故答案为:(1)①B;②D;③A;④C;(2)具有可燃性,与空气混合遇明火可能爆炸;化学;密度比空气小,化学性质很不活泼.

阅读理解

Some inventions are so useful, but seem so simple, that we wonder why no one thought of them long ago. Post-it Notes, the pieces of paper that you can fasten almost anywhere and then remove without leaving any sign that they were there, are an example of such an invention.

  Post-it Notes were invented about twenty years ago by Art Fry, a scientist at 3M Corporation. The idea for the product came from a frustrating experience he often had while singing in his church choir. Fry used pieces of paper as bookmarks to mark the places in his book of songs, but these bookmarks were always falling out. He knew he needed a bookmark that would stay where he put it, but that he could remove without damaging the pages.

  Around that time, Fry heard about a new adhesive (粘合剂) that a workmate, Dr. Spence Silver, had created. This adhesive was special because it was sticky, but not too sticky. It was strong enough to hold papers together, but weak enough to not tear the paper when it was removed. Fry saw that the new adhesive could help solve his bookmark problem. One morning, Fry put some of the adhesive on the edge of a piece of paper. Just as he hoped, it made a perfect bookmark.

A short time later, Fry realized that his new invention had even more uses than being a great bookmark. He came to this realization when he wrote a note on one of his new "bookmarks" and attached it to a report he was going to give to a workmate. Soon, co-workers were asking Fry for more samples of his invention so that they could use the new type of notes themselves.

  Fry and some other people at 3M believed so much in the new product that they persuaded the company to give away thousands of the "sticky pieces of paper" for trial use(试用). When some salespeople at 3M went to offices and showed workers just how helpful the new type of notes could be, they immediately received many orders. As more and more people discovered how useful Post-it Notes could be, the product took off.

小题1:The invention of Post-it Notes showed that Art Fry________ .

A.had a lot of knowledge

B.was very hard-working

C.was good at creative thinking

D.loved his job in the church小题2: In what way did Dr. Spence help Art Fry?

A.They worked together and often discussed science.

B.His invention of a special adhesive made Art's invention possible.

C.He advised 3M Corporation to give away lots of Post-it Notes for trial use.

D.He worked together with Art by providing the new adhesive for Art.小题3: The underlined phrase "took off" means_______ .

A.started to leave the ground

B.disappeared from the market

C.had even more uses

D.became popular very quickly小题4:The biggest advantage of Post-it Notes is_______.

A.it can stay anywhere and leave no sign when removed  

B.it is very cheap to use  

C.it is good to write notes on

D.it is very thin and beautiful

单项选择题