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1.某研究性学习小组为研究Cu与浓H2SO4的反应,设计如下实验探究方案(装置中的固定仪器和酒精灯均未画出)

实验选用细铜丝、98.3% H2SO4、品红溶液、澄清石灰水、CCl4、NaOH溶液等药品,铜丝被卷成螺旋状,一端没入浓H2SO4中,另一端露置在液面上方。


 
以下是该学习小组部分交流记录及后续探究实验的记录

根据上述材料回答下列问题

(1)A试管上方的长导管的作用是_________________;D、E两支试管中CCl4的作用是_____________。

(2)加热过程中,观察到A试管中出现大量白色烟雾,起初部分烟雾在试管上部内壁析出淡黄色固体物质,在持续加热浓硫酸(沸腾)时,淡黄色固体物质又慢慢地消失。写出淡黄色固体消失的化学反应方程式:____。

(3)对A试管中的浓H2SO4和铜丝进行加热,很快发现C试管中品红溶液褪色,但始终未见D试管中澄清石灰水出现浑浊或沉淀。你的猜想是:________      ___  。

设计实验验证你的猜想________________                   

(4)根据上述研究,结合所学知识,你认为液面下方铜丝表面的黑色物质成分是_____。(写化学式)

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距离高考剩下不到半年的时间了,紧张的高考备考早已拉开序幕,但是很多同学还不知如何处理学习、健身和休息与高考备考之间的关系请根据图中的内容写一篇英语短文,谈一谈你对这一问题的看法或建议

注意:

1.    词数120字左右,开头语已为你写好;

2.    可适当增加细节,以使行文连贯

(注意:超出方框部分不给分)

How to Get Prepared for the College Entrance Exams
We are going to attend the College Entrance Exams in less than 6  months._______________________________________________________________________
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________

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8. They set up a monument ____ ________ _______(纪念) the soldiers who died in the Anti-Japanese War.

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7. The picture ______ ______ _______(使我想起) my childhood.

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6. Which driver was ______ _______ (负责) for the accident?

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5. He has got a big room so he is not too ______ ______(贫穷).

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4. They were wet to the skin because they _______ ________ ________(遇上) a shower on the way.

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3. We must ______ our attention _______ efficiency(集中).

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2. He’s giving her French lessons _____ _______ _______(交换) her teaching him Chinese.

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1. Don’t ________ ________ _______ (瞧不起) a person only because he has failed in an exam.

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