问题 选择题

下列离子方程式正确的是         (   )

A.纯碱溶液显碱性的化学原理:CO32+2H2O H2CO3+2OH

B.在偏铝酸钾溶液中滴加入足量稀盐酸:AlO2+H++H2O=Al(OH)3

C.澄清石灰水中通入少量CO2气体:Ca2++2OH+CO2=CaCO3↓+H2O

D.Fe粉与足量稀硝酸反应:3Fe+8H++2NO3=3Fe2++2NO↑+4 H2O

答案

答案:C

A.多元弱酸盐水解分步进行,且以第一步为主:CO32+H2O HCO3+OH

B.得到的Al(OH)3沉淀会溶于强酸:AlO2+4H+=Al3++2H2O

C.正确

D.稀硝酸过量,铁只能以Fe3+形式存在:Fe+4H++NO3=Fe3++NO↑+2H2O

阅读理解

Can you swim? Do you like swimming? Yes? Well, how can you learn to swim? I think the best way is to go into the water and learn. I’m afraid you’ll never learn to swim just by reading books about swimming or looking at others swimming. It’s the same with the English study. We must practice, practice and practice.

Listening and speaking are very important for beginners. The children in English-speaking countries first listen to others. Then they try to imitate and speak. We can listen to English programs on radio. You may just understand a few words. It doesn’t matter. Just be relaxed, try to catch every word. Somebody may be a good listener. But he dare not speak. He’s afraid of making mistakes. You know we sometimes make mistakes when we speak Chinese. Don’t be afraid. We must be brave. If you really want to learn English well, you must try to speak with everyone as long as he knows English. Whether you know him or not is not important, when there’s nobody to talk with, you can talk to yourself in English. It’s interesting and also a good way to practice your spoken English. Remember, the more you speak, the fewer mistakes you’ll make.

Reading and writing are more important for senior school students. First we must choose the books we’re interested in. A lot of reading will improve your language sense. This is the most important.

Keep writing English diaries. We can also write English articles. You may even post them to English magazines. Don’t be afraid of failure. Failure is the mother of success.

Easier said than done. Well, let’s do more practice from now on. I’m sure you’ll learn English well in this way.

小题1:You can learn to swim by_______.

A.reading books about it

B.looking at others swimming

C.having lessons on it

D.going into the river and learning小题2:We should learn English by _______.

A.listening and speaking

B.reading and writing

C.both A and B

D.swimming小题3:What will you do with mistakes when you speak?

A.Don’t make mistakes.

B.Study hard

C.Try not to speak English

D.Don’t be afraid.小题4:What’s more important for senior school students?

A.listening

B.speaking

C.reading and writing

D.learning小题5:We can listen to English ______, according to the passage.

A.by train

B.on the radio

C.every minute

D.now and then

单项选择题