问题 填空题

请根据下列内容回答问题:

(1) 常用来作致冷剂的干冰是_____ (填化学式),干冰易___________ (填物理学名词),这一   过程____ (填“吸收”或“放出”)热量,因此可作致冷剂;  

(2) 泡沫灭火器的工作原理是______ (用化学方程式表示);  

(3) 炎热的夏日里,我们常常饮用碳酸饮料,碳酸饮料在生产的过程中要用加压的方法将二   氧化碳气体压入水中,这样做的原因是__________ ;  

(4) 为促进作物生长,增加粮食产量,人们常常向温室内通入二氧化碳,这样做的目的是___

答案

(1)CO 升华  吸热

(2)NaCO3+2HCl=2NaCl+H2O+CO2↑  

(3)使更多的CO2溶于水中,且跟水反应生成碳酸  

(4)促进

阅读理解

“Everything happens for the best,” my mother said whenever I was disappointed. “If you go on, one day something good will happen.” When I graduated from college, I decided to try for a job in a radio station and then work hard to become a sports announcer (广播员).

I took a taxi to Chicago and knocked on the door of every station, but I was turned down every time because I didn’t have any working experience. Then, I went back home.

My father said Montgomery Ward wanted a sports-man to help them. I applied (申请), but I didn’t get the job, either. I was very disappointed.“Everything happens for the best,” Mom reminded me. Dad let me drive his car to look for jobs. I tried WOC Radio in Davenport, Iowa. The program director, Peter MacArthur, told me they had already had an announcer. His words made me disappointed again. After leaving his office, I was waiting for the elevator when I heard MacArthur calling after me, “What did you say about sports? Do you know anything about football?” Then he asked me to broadcast an imaginary (虚构的) game. I did so and Peter told me that I would be broadcasting Saturday’s game!

On my way home, I thought of my mother’s words again:“If you go on, one day something good will happen.”

小题1:What kind of job did the writer want to get after he graduated from college?

A.A programmer.

B.A sports announcer.

C.A sportsman.

D.A taxi driver.小题2:Why couldn’t the writer get a job at first?

A.Because he didn’t want to get it.

B.Because he didn’t have any experience.

C.Because his parents didn’t agree with him.

D.Because no stations needed an announcer.小题3: Every time the writer couldn’t get a job, his mother ________.

A.said nothing to him

B.told him to give up

C.encouraged him to go on trying

D.advised him to get further education小题4:The underlined phrase “turned down” is closest in meaning to the word “______”.

A.asked

B.invited

C.refused

D.taken小题5:Which of the following is NOT true about the writer in the passage?

A.He disliked the job in Montgomery Ward.

B.He got a good job in Davenport, Iowa at last.

C.He was given a chance by Peter.

D.His father also gave him some help.

单项选择题