问题 完形填空
完形填空.
     Mr and Mrs Jones usually __1__ go out in the evening. But last Saturday, Mrs. Jones __2__ to
Mr. Jones,"There's a good film at the cinema this __3__. Can we go and __4__ it?"
     Mr. Jones was quite __5__ about it, so they went and __6__ it.
     They came out of the cinema__7__ o'clock, got into the car, and began __8__ home. It was very
__9__. Then Mrs. Jones said, " Look, Bill. A woman is _10__ very fast, and a man is running __11_
her. Can you see them?" Mr. Jones said, "Yes, I can." He drove the car near the woman and said to her,
"Can we help you?" "No, thank you," the woman said but she didn't stop _12__, " My husband and I
always run _13__ after the _14__ , and the last one _15__ the house. "
( )1. A. does    
( )2. A. said    
( )3. A. moming  
( )4. A. see      
( )5. A. pleased  
( )6. A. watch    
( )7. A. in      
( )8. A. togo    
( )9. A. black    
( )10. A. running
( )11. A. to      
( )12. A. to run  
( )13. A. home    
( )14. A. car    
( )15. A. clean  
B. don't    
B. sayed    
B. aftemoon  
B. watch    
B. pleasant  
B. see      
B. on        
B. going    
B. dark      
B. run      
B. for      
B. running  
B. to home  
B. me        
B. cleans    
C. didn't  
C. says    
C. evening  
C. look    
C. pleasure
C. enjoyed  
C. at      
C. driving  
C. deep    
C. to run  
C. after    
C. run      
C. of      
C. cinema  
C. cleaning
答案

1-5: BACAA    6-10: CCCBA    11-15: CBACB

填空题

Na2CO3和H2O2结合成棒状晶体,Na2CO3·xH2O2(过氧化氢合相当于水合。注意:使用高浓度H2O2时一定要小心,防止爆炸生成水和氧气),可消毒、漂白或作O2源…。现称取一定质量的Na2CO3·xH2O2晶体加热。实验结果以温度和相对质量分数示于下图。

(1)该棒状晶体的化学式Na2CO3·xH2O2中x=_____________。

(2)加热过程中,在141℃时表现为放热,其原因可能是:_______________ 

a. Na2CO3·xH2O2分解放热                 

b. 产生的H2O2分解放热  

c. Na2CO3·xH2O2分解吸收热量小于产生的H2O2分解放出的热量

(3)事实上,Na2CO3·H2O2(x=1时)是Na2CO4·H2O(Na2CO4叫做过氧碳酸钠)。洗衣粉中加入适量的Na2CO4可以提高洗涤质量,其目的是对衣物进行漂白、消毒。试用化学方程式表示上述洗涤原理______________________。

(4)写出Na2CO4溶液与稀硫酸反应的离子方程式__________________。

(5)下列物质不会使过碳酸钠失效的是_____________      

A、 MnO2          B、H2S          C、CH3COOH         D、NaHCO3

(6)Na2O2、K2O2、CaO2以及BaO2都可与酸作用生成过氧化氢,目前实验室制取过氧化氢的水溶液可通过上述某种过氧化物与适量稀硫酸作用,最适合的过氧化物是___________,原因是_______________。要使获得的过氧化氢从其水溶液中分离出来,采取的措施是___________________ 。

(7)写出过氧酸根的等电子体____________________(一到二种)

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