问题 问答题

某些化学反应可用下式表示:A+B→C+D+H2O.请回答下列问题:

(1)若A、C、D均含有氯元素,且A的化合价介于C与D之间,写出该反应的离子方程式:______.

(2)若C、D均为气体且都能使澄清石灰水变浑浊,则A与B的组合为______.

(3)若A为黑色固体,C是黄绿色的单质气体,写出该反应的离子方程式:______.

(4)若A为Na2O2,B为硫酸,则C和D的化学式为______.

(5)若A、C均含有铝元素.则C可能为______或______.

(6)若A为有颜色的金属单质,B为第二周期某种元素的最高价氧化物的水化物,请写出符合上式的化学方程式:______.

答案

(1)A、C、D中均含有氯元素,且A中的Cl的化合价介于C和D之间,该反应为氯气在碱性条件下的歧化反应,反应的离子方程式为Cl2+2OH-═Cl-+ClO-+H2O,

故答案为:Cl2+2OH-=Cl-+ClO-+H2O;

(2)能使澄清的石灰水变浑浊的气体有SO2和CO2,应为碳和浓硫酸的反应,则A与B的组合为C和浓H2SO4

故答案为:C、浓H2SO4

(3)应为MnO2和浓盐酸的反应,生成黄绿色气体为Cl2,反应的离子方程式为MnO2+4H++2Cl-

 △ 
.
 
Mn2++Cl2↑+2H2O,

故答案为:MnO2+4H++2Cl-

 △ 
.
 
Mn2++Cl2↑+2H2O;

(4)若A为Na2O2,B为硫酸,生成Na2SO4和O2,则C和D的化学式为Na2SO4、O2,故答案为:Na2SO4、O2

(5)若A、C均含有铝元素,生成水,可为AlCl3与过量强碱或NaAlO2与过量强酸的反应,C可能为AlCl3或NaAlO2

故答案为:AlCl3;NaAlO2

(6)B为第二周期某种元素的最高价氧化物的水化物,只能为HNO3,则A为Cu,发生反应的方程式为

Cu+4HNO3(浓)=Cu(NO32+2NO2↑+2H2O[或3Cu+8HNO3(稀)=3Cu(NO32+2NO↑+4H2O],

故答案为:Cu+4HNO3(浓)=Cu(NO32+2NO2↑+2H2O[或3Cu+8HNO3(稀)=3Cu(NO32+2NO↑+4H2O].

完形填空
完形填空。
     I ever had my best lesson years ago.
     In my class, Mark talked all the time. I had to tell him again and again that    1   in class was not right.
Every time he said sincerely, "Thank you for correcting me, Madam." I didn't know what to do, but soon I 
   2    to hearing it many times a day.
     Like Mark, the other students were noisy. One afternoon, when everyone was having    3    with a math
problem, some students started to fight. I had to do something, so I asked each student to get out thirty-four
small pieces of paper. I told them    4   they should write the name of a    5    on each piece and, under that,
say something nice about the person. At the end of class I    6    the papers. At the beginning of the next day
I gave them out to the students. Everyone smiled. Their classmates had said such    7    things about them!
The exercise had achieved its aim. The students were happy with themselves and one another again.
     Many years    8   , Mark's father called to tell me Mark was killed in the war and asked me to his funeral
(葬礼) the next day. At the funeral Mark's father came up to me and took out some papers.    9    looking at
the papers, I knew they were the   10   on which Mark's classmates had listed all the nice things about him.
( )1. A. telling  
( )2. A. used    
( )3. A. difficulty 
( )4. A. that    
( )5. A. teacher  
( )6. A. invented  
( )7. A. nice    
( )8. A. ago    
( )9. A. Because  
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B. got used   
B. difficult 
B.what     
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B. discovered   
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B. Don't     
B. it      
C. speaking    
C. liked       
C. different   
C. if        
C. parents    
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C. those     
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D. enjoyed         
D. difference  
D. why           
D. people          
D. collected                    
D. terrible    
D. after         
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选择题