问题 选择题

化合物HIn在水溶液中因存在以下电离平衡,故可用作酸碱指示剂

HIn(红色溶液)  H(溶液)+ In(黄色溶液)

浓度为0.02 mol·L1的下列各溶液: ①盐酸②石灰水③NaCl溶液 ④NaHSO4溶液 ⑤NaHCO3溶液 ⑥氨水,⑦AlCl3溶液其中能使指示剂显红色的是

答案

答案:C

题目分析:向溶液中加盐酸、硫酸氢钠溶液、氯化铝(水解生成盐酸)溶液c(H+)都增大,平衡向左移动,指示剂显红色;向溶液中加石灰水、碳酸氢钠溶液(水解生成氢氧化钠)、氨水c(OH-)都增大,平衡向右移动,溶液显黄色;溶液中加入氯化钠溶液平衡不移动,溶液显橙色。

点评:硫酸氢钠在水溶液中相当于一元酸。

完形填空
完形填空
       It was winter, and Mrs Hermann wanted to do a lot of shopping, so she waited   1    it was Saturday. When her husband   2   , she took him to the shops with her to pay(付款)for everything and to carry her
bags. They went to a lot of shops, and Mrs Hermann    3   a lot of things. She often   4   and said, "Look,
Joe! Isn't that beautiful?" He then answered,"All right, dear. How   5   is it?"And took his money   6    to
pay for it. It was dark when they came out of the last   7     and Mr Hermann was very   8   and thinking
about other things, like a nice drink at home. Suddenly his wife looked up at the sky and said,"Look   9   
that beautiful moon, Joe! "   10   stopping, Mr Hermann answered,"All right. How much is it?"
( )1. A. until      
( )2. A. is free    
( )3. A. sold        
( )4. A. stops      
( )5. A. many        
( )6. A. of          
( )7. A. house      
( )8. A. happy      
( )9. A. for        
( )10.A. With        
B. after        
B. was free    
B. made        
B. is stopping  
B. heavy        
B. out          
B. shop        
B. sad          
B. after        
B. Within      
C. when      
C. free      
C. borrowed  
C. stopped    
C. much      
C. from      
C. factory    
C. busy      
C. at        
C. Without    
D. because          
D. would be free    
D. bought          
D. stoped          
D. big              
D. into            
D. park            
D. tired            
D. around          
D. Whether          
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