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问题 选择题

在已经处于化学平衡状态的体系中，如果下列量发生变化，其中一定能表明平衡移动的是（  ）

　 

A．反应混和物的浓度

B．正、逆反应速率

　

C．反应混和物的压强

D．反应混合物中各物质的百分含量

答案

答案：D

正确答案：D

在一定条件下，当一个可逆反应的正反应速率与逆反应速率相等时，反应物的浓度与生成物的浓度不再改变，达到一种表面静止的状态，即"化学平衡状态". 其中，正反应速率与逆反应速率相等是化学平衡状态的实质，而反应物的浓度与生成物的浓度不再改变是化学平衡状态的表现。正反应速率与逆反应速率是针对同一可逆反应而言，正与反只是相对而言，不是绝对概念。

A 、不正确，反应混和物的浓度，可能因为体积缩小而增大

B、不正确，正、逆反应速率，可能因为加入催化剂面加快

C 、不正确，反应混和物的压强可能因为加入不参加反应的物质改变

单项选择题

Culture is activity of thought, and receptiveness to beauty and human feeling. (1) of information have nothing to do with it. A merely well-informed man is the most useless (2) on God’s earth. What we should (3) at producing is men who (4) both culture and expert knowledge in some special direction. Their expert knowledge will give them the ground to start (5) , and their culture will lead them as (6) as philosophy and as high as (7) We have to remember that the valuable (8) development is self-development, and that it (9) takes place between the ages of sixteen and thirty. As to training, the most important part is given by mothers before the age of twelve.

In training a child to activity of thought, above all things we must (10) of what I will call "inert ideas"—— that is to say, ideas that are merely (11) into the mind without being (12) , or tested, or thrown into fresh combinations.

In the history of education, the most (13) phenomenon is that schools of learning, which at one epoch are alive with a craze for genius, in a (14) generation exhibit merely pedantry and routine. The reason is that they are overlade with inert ideas. Except at (15) intervals of intellectual motivation, education in the past has been radically (16) with inert ideas. That is the reason why (17) clever women, who have seen much of the world, are in middle life so much the most cultured part of the community. They have been saved from this horrible (18) of inert ideas. Every intellectual revolution which has ever stirred humanity (19) greatness has been a (20) protest against inert ideas.

17（）

A.unrefined

B.unintended

C.unrestrained

D.uneducated
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填空题 案例分析题

下图表示蛋白质合成过程的某个阶段，据图分析并回答问题：

根据上图并参考右上表分析：[1]（）上携带的氨基酸是（），这个氨基酸与之前的氨基酸是通过（）反应连接在一起的。
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