摘要: 呈--的形状 16.virtual reality

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Men have always wondered about the earth they live on and about the ①_____ above them.

         When early men looked at the night sky, they asked themselves a lot of questions. They looked at the moon, and wondered what this strange bright object in the sky was. They did not understand why it changed its shape from night to night. They looked at the stars and planets. They also wondered why some of them changed their positions, while others did not.

         ②他们也思考地球的形状。 Most early people believed the earth was flat.

         ③In different parts of the world, there were different ideas about the universe. The ancient Greeks were the first people to study the universe more scientifically. In the sixth century BC Pythagoras put forward the idea that the world was round. However, he could not explain why people at the bottom of the world did not fall off.

         It was not until the sixteenth and seventeenth centuries that scientists found the answers to some important questions. ④With the help of Galileo’s telescope, people could see the sky more clearly, and find the positions of the stars and planets. Finally in 1665, Isaac Newton explained to the world what gravity (重力) was and people at last understood why they did not fall off the earth.

1.在文中①处填写一个单词,使得句意完整、上下文通顺。___________________

2.根据文章内容回答问题。

What questions did early men ask themselves when they looked at the night sky? Write down one of them.

_________________________________________________________________________

3.将文中②句翻译成英语。

_________________________________________________________________________

4.将文中③句翻译成汉语。

_________________________________________________________________________

5.写出文中④句的同义句,每空限填一词。

Galileo’s telescope made _________________ for people to see the sky more clearly, and to find the positions of the stars and planets.

 

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Cu的化合物在生活及科研中有重要作用,不同反应可制得不同状态的Cu2O
(1)科学研究发现纳米级的Cu2O可作为太阳光分解水的催化剂。
①在加热条件下用液态肼(N2H4)还原新制Cu(OH)2可制备纳米级Cu2O,同时放出N2。当收集的N2体积为3.36L(已换算为标准状况)时,可制备纳米级Cu2O的质量为        

②一定温度下,在2 L密闭容器中加入纳米级Cu2O并通入0.20 mol水蒸气,发生反应:
  ;测得20 min时O2的物质的量为0.0016 mol,则前20 min的反应速率v(H2O)=                  ;该温度下,反应的平衡常数表达式K=                  ;下图表示在t1时刻达到平衡后,只改变一个条件又达到平衡的不同时段内,H2的浓度随时间变化的情况,则t1时平衡的移动方向为      ,t2时改变的条件可能为              ;若以K1、K2、K3分别表示t1时刻起改变条件的三个时间段内的平衡常数,t3时刻没有加入或减少体系中的任何物质,则K1、K2、K3的关系为                
(2)已知:ΔH=-293kJ·mol-1           
ΔH=-221kJ·mol-1
请写出用足量炭粉还原CuO(s)制备Cu2O(s)的热化学方程式        
(3)用电解法也可制备Cu2O。原理如右上图所示,则阳极电极反应可以表示为        
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