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问题 问答题

如图是实验室用双氧水和二氧化锰制取氧气及探究其化学性质的装置图：

请回答：

（1）写出标号①仪器的名称是______．

（2）实验室制取氧气应选用的发生装置是______；收集装置可选用D装置，理由是______；如果用E装置收集氧气，气体应从______（填“a”或“b”）进入．

（3）写出实验室制取氧气的化学方程式______．

（4）观察F装置中的实验现象：红磷在氧气中剧烈燃烧，产生大量白烟，这是因为生成了______（填化学式）的固体小颗粒的缘故．

（5）写出G中乙炔______完全燃烧的化学方程式______．

答案

（1）①是水槽；

（2）实验室用过氧化氢溶液制取氧气属于固液常温型，但要注意长颈漏斗的末端要伸入液面以下，所以选择A装置；能用D装置收集氧气是因为氧气的密度比空气大；因为氧气难溶于水，故应该从短管a进入，利用气压把水从长管排出；

（3）过氧化氢在二氧化锰的作用下分解成水和氧气，反应的方程式为：2H2O2

MnO2
.
2H2O+O2↑；

（4）白磷燃烧产生的白烟是五氧化二磷固体小颗粒形成的，化学式为：P2O5 ；

（5）乙炔的化学式为：C2H2；反应的方程式为：2C2H2+5O2

点燃
.
2H2O+4CO2；

故答案为：（1）水槽； （2）A 氧气的密度比空气的密度大 a；（3）2H2O2

MnO2
.
2H2O+O2↑；

（4）P2O5 （5）C2H2 2C2H2+5O2

点燃
.
2H2O+4CO2

单项选择题

某人因违章作业造成事故，则该人为这起事故的( )责任者。

A．直接

B．主要

C．领导

D．间接
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完形填空
完形填空。
     Although I love my life, it hasn't been a lot of fun as I've been ill for 28 years.
     Music has always been a great love of mine and, in my 20s, when my   1   was more manageable, I  2   ten
years as a professional singer in restaurants, playing and singing folk songs.   3   that was years ago and times
have changed.   4   I live with mother on a country farm.
     Two years ago, I decided that I would need to have some kind of extra work to   5   my disability pension
(残疾抚恤金).   6   I needed to sleep in the afternoons, I was limited in my   7  . I decided that I would consider 
  8   to singing in restaurants.
     My family are all musicians, so I was   9   when I went into our local music store. I explained that I wanted
to sing again but using recorded karaoke music. I knew that discs were very expensive and I really didn't have
a lot of  10  to get started. And  11  you find only three to four songs out of ten on a disc that you can  12  use.
     When I told the owner of the shop about my  13 ; he gave me a long thoughtful  14 . "This means a lot to
you, doesn't it?" he said. "Come with me."
     He led me  15  the crowded shop and to a bench with a large professional karaoke box on it. He placed his
large hand  16  on his treasure and said, "I have 800 karaoke songs in here. You can take your  17  and I'll record
them for you. That should get you started."
     I  18 . Thanking him, I made a time with him to listen to all the songs and choose  19  that I could sing. I
have come full circle with his help.
     His  20  still warms my heart and makes me do just that bit extra, when I have the chance.
( )1. A. loneliness   
( )2. A. set       
( )3. A. Gladly      
( )4. A. Now       
( )5. A. add up to    
( )6. A. If        
( )7. A. movement    
( )8. A. reaching out
( )9. A. recognized   
( )10. A. money     
( )11. A. thus       
( )12. A. actually    
( )13. A. job       
( )14. A. face       
( )15. A. over       
( )16. A. unhappily   
( )17. A. pick       
( )18. A. had to cry   
( )19. A. more      
( )20. A. courage   		B. sadness    
B. enjoyed    
B. Eventually  
B. Then     
B. make up for  
B. As       
B. condition   
B. living up   
B. interviewed  
B. time    
B. once     
B. hardly    
B. family    
B. view     
B. along     
B. lovingly   
B. turn    
B. ought to cry   
B. the ones   
B. devotion   		C. tiredness      
C. kept         
C. Unfortunately    
C. Sometime      
C. get rid of     
C. Though         
C. choices        
C. getting on      
C. found          
C. energy        
C. seldom        
C. nearly        
C. idea          
C. look         
C. towards        
C. pitifully      
C. role         
C. should have cried  
C. few           
C. kindness       		D. sickness         
D. shared           
D. Surprisingly     
D. Meanwhile        
D. take advantage of       
D. Before           
D. positions        
D. going back       
D. invited          
D. knowledge        
D. often            
D. formerly         
D. offer            
D. sight            
D. through          
D. gratefully       
D. step             
D. could have cried
D. the rest         
D. trust            
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