在各种条件下in all situations 查看更多

 

题目列表(包括答案和解析)

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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有机物甲分子式为C11H14O2,在酸性条件下水解生成乙和丙,丙遇FeCl3溶液显紫色,丙的相对分子质量比乙大20,甲的结构有   (   )
A.6种B.4种C.3种D.8种

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(12分)下述反应中,属于氧化反应的是                    ,属于取代反应的是               ,属于加成反应的是                    
①乙醇在铜催化加热 条件下制乙醛的反应                
②乙烷在光照条件下与氯气反应
③乙烯使酸性高锰酸钾溶液褪色                      
④乙烯使溴水褪色
⑤苯与浓硝酸、浓硫酸混合共热制取硝基苯               
⑥乙酸和CH3CH218OH在浓硫酸加热条件下生成酯的反应
⑦苯在一定条件下与氢气的反应
写出反应的方程式:①                           

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人人都有朋友 初中三年同学之间结下深厚的友谊。假设你叫张华,你的笔友李敏在下面这封信中介绍了他的学友,请你写一封70 词左右的回信,说说你好友的基本情况和兴趣爱好。

注意:1、回信的开头和结尾已给出.但不计入总词教:

      2、信中请勿使用朋友的真实校名和姓名

Dear Zhang Hua.

    How are you? In this letter I’d like to say something about my best friend.

    My best friend is Gao Jun. He is fifteen. He is tall with short hair. We are in the same class.

    Gao Jun is smart and friendly in class, he listens to the teachers carefully At home, he often helps his mother with housework He does well in all his lessons. And he is always ready to help others. So, everyone in our class likes him

    Gao Jun seems to have a special interest in writing. He wants to be a writer in the future.

    Both of us like playing basketball .We usually play it after class. We feel happy when we are together. I think we will be good friends forever.

    What about your best friend? Can you tell me something about him( her)?

                                                     Yours.

                                                      Li Min.

Dear Li Min.

Thank you for telling me so much about your best friend Gao Jun.

__________________________________________________________________________

__________________________________________________________________________

__________________________________________________________________________

                                                                 Yours.

                                                        Zhang Hua

 

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书面表达

假如昨天你们班以“Should We Keep Animals in Zoos? ”为开展了一次英语讨论,请根据下表用英语写一篇80词左右的报道,介绍讨论会的大概情况,第一句已给出,不计入词数。

20 students

Should keep animals in zoo

人们可以在动物园里看到很多种类的动物(all kinds of )。

动物们在动物园里可以得到很好的照顾(take good care of)。

30 students

Shouldn’t keep animals in zoo

动物们被关在笼子(keep in the cage)里,无法获得自由(get freedom)。

动物喜欢生活在自然环境中(live in the nature)

Your opinion

Yesterday we had a discussion about if we should keep animals in zoos.  ____________________

_______________________________________________________________________________________

_______________________________________________________________________________________

_______________________________________________________________________________________

_______________________________________________________________________________________

 

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