问题 填空题

铜是生命必需的元素,也是人类最早使用的金属之一,铜的生产和使用对国计民生各个方面产生了深远的影响。在化学反应中,铜元素可表现为0、+1、+2价。

(1)在西汉古籍中曾有记载:曾青得铁则化为铜[即:曾青(CuSO4)跟铁反应就生成铜]。试写出该反应的化学方程式:___________________________。  

(2)铜器表面有时会生成铜绿[Cu2(OH)2CO3],这层铜绿可用化学方法除去。试写出除去铜绿而不损伤器物的反应的化学方程式:___________________________。  

(3)新制的铜试剂[Cu(OH)2]与葡萄糖反应会生成红色沉淀,因此该试剂可用于检验糖尿病人尿液中葡萄糖的含量。葡萄糖的结构简式如下:

试写出GCHO与Cu(OH)2反应的化学方程式:___________________________。

答案

(1)CuSO4+Fe=FeSO4+Cu  

(2)Cu2(OH)2CO3+4HCl=2CuCl2+3H2O+CO2↑或Cu2(OH)2CO3+2H2SO4=2CuSO4+3H2O+CO2

(3)GCHO+2Cu(OH)2GCOOH+Cu2O+2H2O

完形填空
完形填空。
      The three superstars were arriving at the airport and a large crowd of young people had already gathered
there to welcome them.The police found it   1   to keep order after the plane landed and the performers   2  .
They smiled and waved cheerfully at everybody.Dressed in the same pink shirts and light blue trousers, with
long hair and musical instruments over their shoulders, they all looked   3  .
     Although there were many policemen   4  , the Blare were not able to get to their waiting car   5   at all.
Word spread that they had composed a new song which would be   6   when they performed at the concert
that evening.They were now    7   with loud cries of" Play your new song! Play your new song!"
     When the stars prepared to sing as the   8   for getting away, even the policemen looked   9  , too. The tans
settled down and listened to the first  10   of the new song.Once it was over, everyone started jumping, clapping
and shouting  11  . Several young women even fainted (昏倒) with excitement and were carried away
immediately by the  12   standing by. The fans were greedy for more,  13  a repeat performance.Once again,
the performers had no choice but to   14  , but when they were asked for still another song, they cheerfully but
firmly refused.Closely   15   by the policemen, they walked towards their car some distance  16  . The fans
pushed forward, but the policemen,   17   arm, prevented anyone getting trough. It took the stars quite a long
time to reach their   18   !
      Finally, however, they all got in and were just about to leave when a young woman, who had somehow 19 
  to gel past the policemen, jumped onto the roof of the car.She shouted loudly and crazily as two policemen
dragged her away and the car started to move very slowly through the   20   crowd.She had just wanted to have
a photo taken with the stars!
( )1. A.dangerous   
( )2. A.arrived     
( )3. A.famous      
( )4. A.present     
( )5. A.successfully
( )6. A.heard       
( )7. A.covered     
( )8. A.way         
( )9. A.pleased     
( )10. A. scene     
( )11. A. loudly    
( )12. A. doctors   
( )13. A. signing   
( )14. A. give cut  
( )15. A. surrounded
( )16. A. out       
( )17. A. stood     
( )18. A. car      
( )19. A. attempted 
( )20. A. shouting  
B. terrible  
B. appeared  
B. nervous   
B. enough    
B. completely          
B. broadcast 
B. greeted   
B. excuse    
B. surprised 
B. part      
B. madly     
B. fans      
B. enjoying  
B. give away 
B. followed  
B. away      
B. fought    
B. theatre   
B. managed   
B. crying    
C. impossible    
C. left            
C. alike         
C. available       
C. easily        
C. received        
C. crowded         
C. gift                         
C. puzzled       
C. sound         
C. strangely       
C. policemen       
C. suggesting      
C. give in         
C. watched       
 C. apart           
C. protected       
C. hotel         
C. started       
C. cheering      
D. difficult     
D. settled       
D. special       
D. serious       
D. directly      
D. tried         
D. called        
D. price         
D. worried                  
D. performance   
D. proudly       
D. workers       
D. demanding     
D. give up       
D. supported     
D. off           
D. locked        
D. group         
D. rushed        
D. pushing       
单项选择题