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问题 选择题

瑞典ASES公司设计的曾用于驱动潜艇的液氨-液氧燃料电池示意图，有关说法正确的是

A．电池工作时，Na＋ 向负极移动

B．电子由电极2经外电路流向电极1

C．电池总反应为：4NH3+3O2＝2N2+6H2O

D．电极2发生的电极反应为：O2+ 4H + + 4e－＝2H2O

答案

答案：C

题目分析：A、原电池中阳离子向正极移动，错误；B、该电池中氧气得到电子所在电极为正极，电极1为负极，电子有负极电极1流向正极电极2，错误；C、正确；D、该电池介质为碱性，不能有氢离子参与反应，错误。

阅读理解

阅读理解。

     My name is Sally White. I am a schoolgirl. My school is far from my home. Every day it takes me a

lot of time to get there. The road is not flat, so I cannot go to school by bike. I often go there by bus or

on foot. It takes me thirty minutes to get there by bus and an hour on foot. I must get up very early every

morning. I have no time for breakfast at home. I often have something for breakfast on the way or on the

bus. I don't want to be late for school, so sometimes I run to school.    

1. What is Sally White? 

                                                                                  

2. How does Sally often go to school? 

                                                                                 

3. How long does it take Sally to go to school on foot? 

                                                                                 

4. Does Sally have breakfast at home?

                                                                                  

5. What does "flat" mean in Chinese?

                                                                              

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单项选择题

属于分布区域缩小，资源处于衰竭状态的重要野生药材是（）

A.羚羊角

B.细辛

C.厚朴

D.党参
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