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问题 填空题

（1）元素S在周期表中的位置是______．

（2）原电池是把______能转变成______能．

（3）断开1molH-H键需______436kJ的能量（填“吸收”或“放出”）．

答案

（1）S的质子数为16，原子结构中有3个电子层，最外层电子数为6，则在元素周期表中的第三周期第ⅥA族，故答案为：第三周期第ⅥA族；

（2）原电池中的能量变化是通过氧化还原反应来实现的，则原电池装置实现了化学能转变为电能，故答案为：化学；电；

（3）因断裂化学键需要吸收能量，则断开1molH-H键需吸收436kJ的能量，故答案为：吸收．

完形填空

Food is very important. Everyone needs to   1 well if he or she wants to have a strong body. Our minds also need a kind of food. This kind of food is   2 . We begin to get knowledge even when we are very young. Small children are     3   in everything around them. They learn   4   while they are watching and listening. When they are getting older. they begin to   5  storybooks, science books, or anything they like.

When they find something new, they have to ask questions and   6  to find out the answers. What’s the best    7  to get knowledge? If we learn   8 ourselves, we will get the most knowledge. If we are    9  getting answers from others and don’t ask why, we will never learn more and understand    10   .

小题1:A. sleep      B. drink        C. cat

小题2:A. sport       B. knowledge    C. meat

小题3:A. interested  B. interesting   C. good

小题4:A. something   B. nothing      C. anything

小题5:A. write      B. learn        C. read

小题6:A. try        B. think        C. wait

小题7:A. place      B. way          C. road

小题8:A. with       B. to           C. by

小题9:A. seldom      B. always       C. sometimes

小题10:A. much       B. well          C. better
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填空题

在PowerPoint2003中，母版工具栏上有两个按钮，分别是关闭和（）。
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