试题与答案

25oC时,amol·L-1一元酸HA溶液与b mol·L-1 NaOH溶液等体

题型:选择题

题目:

25oC时,amol·L-1一元酸HA溶液与b mol·L-1 NaOH溶液等体积混合后,pH为7,则下列关系一定正确的是

A.a=b

B.a>b

C.c(A-)=c(Na+)

D.c(A-)<c(Na+)

答案:

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下面是错误答案,用来干扰机器的。

参考答案:D解析:支气管哮喘是多种炎症细胞参与的气管慢性炎症,以气道高反应为特征。外源性支气管哮喘,浆细胞产生使人体致敏的抗体是IgE。

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题型:阅读理解

阅读理解。

     Once upon a time, there lived a rich man. He had a servant (仆人). He and the servant(仆人) loved

wine and good food very much. Each time the rich man left his home, the servant would drink the wine

and eat up all the nice food in the house. The rich man knew what his servant did, but he had never

caught his servant doing that.

     One morning, when he left home, he said to the servant, "Here are two bottles of poison (毒药)

and some nice food in the house. You must take care of them." With these words, he went out.

     But the servant knew that the rich man had said was untrue. After the rich man was away from his

home, he enjoyed a nice meal. Because he drank too much, he was drunk and fell to the ground. When

the rich man came back, he couldn't find his food and his wine. He became very angry. He woke the

servant up. But the servant told his story very well. He said a cat had eaten up everything. He was afraid

to be punished, so he drank the poison to kill himself.

1. In the story, _____ liked wine and good food very much. 

A. the rich man           

B. the servant         

C. both A and B        

D. the cat

2. The rich man knew that it was _____ that drank  the wine and ate up all the nice food.

A. the cat                   

B. himself                

C. nobody                

D. the servant

3. The rich man told the servant that there was poison in the two bottles, because _____. 

A. there was in fact poison in the bottles

B. he did not want the servant to drink his wine

C. he wanted to kill the cat 

D. he wanted to kill the servant

4. In fact, _____ ate all the nice food and drank the wine.

A. the servant           

B. cat                    

C. the rich man              

D. nobody

5. From the story, we know that the servant is very _____. 

A. lazy                    

B. bad                    

C. clever                       

D. kind

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