硝酸是一种重要的化工原料,工业上生产硝酸的主要过程如下: (1)以N2和H2为原

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问题:

硝酸是一种重要的化工原料,工业上生产硝酸的主要过程如下:

(1)以N2和H2为原料合成氨气。一定温度下,在密闭容器中充入1molN2和3molH2发生反应。若容器容积恒定,达到平衡状态时,气体的总物质的量是原来的11/12,则N2的转化率α1____________;若容器压强恒定,达到平衡状态时,N2的转化率为α2,则α2 _______α1(‘填“>”、“<”或“=”)。

(2)用氨催化氧化法可生产硝酸,其生产过程可表示为:

4NH3+5O24NO+6H2O,4NO+3O2+2H2O=4HNO3

现以5.1吨液氨为原料来生产质量分数为50%的硝酸,理论上需要加水的质量为_____________吨。(假设生产过程中反应物和生成物均无损耗)

(3)硝酸工业生产中的尾气可用纯碱溶液吸收,有关的化学反应为:

2NO2+Na2CO3=NaNO2+NaNO3+CO2,NO+NO2+Na2CO3=2NaNO2+CO2。若在标准状况下有NO、NO2的混合气体(不考虑N2O4)恰好与50mL 1.0 mol·L-1的Na2CO3溶液反应完全,且生成NaNO2和NaNO3的物质的量的比为4:1,则在混合气体中NO气体的体积分数为多少?(请写出计算过程)

考点:化学平衡的有关计算金属、非金属的有关计算
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哈尔滨市(约45°N)位于

A.回归线和南极圈之间

B.北温带地区

C.南回归线和北回归线之间

D.寒带地区

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适于外墙面装修的种类有()。

A.抹灰类

B.涂刷类

C.卷材类

D.镶钉类

E.贴面类

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任务型阅读 根据所读内容在文章后表格中的空格里填入一个最恰当的单词。(共10小题,每小题1分,计10分)
注意:每个空格只填1个单词。请将答案写在答题卡相应题号的横线上。
Many people think a telephone is a necessity. But I think it is a pest (有害的事物) and a time waste. Very often you find it impossible to escape from it. If you have a telephone in your own house, you will admit that it tends to ring when you least want it to ring; when you are asleep, or in the middle of a meal or a conversation or when you are just going out, or when you are in your bath. Are you strong-minded enough to ignore it? You are not. You think there may be some important news or message for you. I can assure you that if a message is really important it will reach you sooner or later. Have you ever rushed crippling from the bath, or chewing from the table, or dazed from the bed, only to be told that you are a wrong number?
But you will say, you need not have your name printed in the telephone directory, and you can have a telephone which is only usable for outgoing calls. Besides, you will say, isn’t it important to have a telephone in case of sudden emergency—illness, accident, or fire? Of course, you are right, but here in a thickly populated country like England one is seldom far from a telephone in case of dreadful necessity.
I think perhaps I had better try to justify (证明是有理的) myself by trying to prove that what I like is good. I admit that in different circumstances—if I were a wealthy and powerful businessperson, for instance, or badly ill and had to lie in bed, I might find a telephone a necessity. But then if I were a taxi-driver I should find a car as necessity. Let me put it another way: there are two things for which the English seem to show particular talent: one is mechanical invention, the other literature. My own business happens to be with the use of words but I see I must now stop using them, for I have had just been handed a slip of paper to say that somebody is waiting to speak to me on the telephone. I think I had better answer it. After all, one never knows, it may be something important.
Title: The 小题1: _____________
Different
   小题2:    about it
Many people
It is    小题3:    when one wants to make a call, especially in time of     小题4:   .
The author
It can     小题5:   time and even be     小题6:  .
Not everyone,   小题7:   a businessperson or a sick person who has to stay in bed, needs it.
I don’t need it because my job is writing.
   小题8:   with it
It always seems to ring when one is doing something else or doesn’t want it to ring.
Almost     小题9:    can ignore it even if they want to.
One    小题10:    to answer it only to find that he is misdialed.
 
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Windows XP中,各分区保存的格式说法正确的为()

A.必须是FAT32格式

B.必须是NTFS格式

C.FAT32和NTFS格式均可

D.FAT32和NTFS格式都不可用

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从群体规模上划分,属于小群体的是()

A.家族

B.村庄

C.家庭

D.企业

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