问题 选择题

下列离子方程式书写正确的是(  )

A.氧化铜与盐酸反应:O2-+2H+═H2O

B.澄清石灰水与稀盐酸反应:Ca(OH)2+2H+═Ca2++2H2O

C.在稀氨水中通入过量CO2:NH3•H2O+CO2═NH4++HCO3-

D.醋酸和氨水反应:H++OH-═H2O

答案

A、氧化铜与盐酸反应的离子方程式为:CuO+2H+═H2O+Cu2+,故A错误;

B、澄清石灰水与稀盐酸反应的离子方程式为:OH-+H+═H2O,故B错误;

C、在稀氨水中通入过量CO2反应的离子方程式为:NH3•H2O+CO2═NH4++HCO3-,故C正确;

D、醋酸和氨水都是弱电解质,醋酸和氨水反应的离子方程式:CH3COOH+NH3•H2O═H2O+CH3COO-+NH4+,故D错误;

故选C.

完形填空
完形填空:从A、B、C中,选择一个最佳答案,使短文意思完整。
     Some years ago, on a hot summer day, a little boy decided to go for a swimming in the river near his
house. He went into the river and was   1   towards the middle, but he didn't find there was an alligator(鳄鱼)in the river. His mother in the house   2   out of the window and saw the alligator come near. She ran
towards the river   3   and shouted(呼喊)at her son. The little boy   4  his mother's voice and swam to his
mother.   5   it was too late. Just as the mother caught her little boy by the arms, the alligator caught his legs. The mother   6   her best to save(拯救)her son. Later, a farmer walking by killed the alligator with his gun. After several weeks in the   7  , the little boy got well. There were scars(伤疤)on his leg and arms. A
newspaper   8   went to interview him and asked if he would   9   him his scars. The boy showed him his
legs. And then   10   a great smile(微笑), he said to the interviewer, "But look at my arms. I have great scars on my arms, too. They're scars of love".
( )1.  A. running
( )2.  A. came
( )3.  A. quickly
( )4.  A. saw
( )5.  A. So
( )6.  A. tried
( )7.  A. restaurant
( )8.  A. reporter
( )9.  A. describe
( )10. A. by

B. swimming
B. took
B. early
B. felt
B. But
B. had
B. hospital
B. worker
B. find
B. without

C. walking    
C. looked      
C. freely      
C. heard      
C. And        
C. put        
C. school      
C. student    
C. show        
C. with        

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