现有等体积的Ba(OH)2、NaOH和NH3·H2O三种溶液，将它们分别与V1

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问题选择题

现有等体积的Ba(OH)₂、NaOH和NH₃·H₂O三种溶液，将它们分别与V₁L、V₂L、V₃L等浓度的盐酸混合，下列说法中正确的是( )

A．若混合前三种溶液pH相等，将它们同等倍数稀释后，则NaOH溶液pH最大

B．若混合前三种溶液pH相等，酸碱恰好完全反应，则V₃>V₁>V₂

C．若混合前三种溶液物质的量浓度相等，酸碱恰好完全反应，则V₁>V₂>V₃

D．若混合前三种溶液物质的量浓度相等，混合后溶液呈中性，则V₁>V₂>V₃

答案

答案：D

A、不正确，NaOH溶液pH与Ba (OH)₂溶液相同，比NH₃·H₂O溶液小；B、不正确，酸碱恰好完全反应，则V₃>V₁=V₂；C、不正确，酸碱恰好完全反应，则V₁>V₂=V₃；D、正确，NH₄Cl溶液呈中性，用的酸少些，混合后溶液呈中性，则V₁>V₂>V₃。选D。

完形填空

Most parents, I suppose, have had the experience of reading a bedtime story to their children. And they must have   11  how difficult it is to write a   12  children’s book. Either the author has aimed too   13 , so that the children can’t follow what is in his (or more often, her) story,   14  the story seems to be talking to the readers.
The best children’s books are   15  very difficult nor very simple, and satisfy both the 16  who hears the story and the adult who   17  it. Unfortunately, there are in fact few books like this,   18  the problem of finding the right bedtime story is not   19  to solve. This may be why many of the books regarded as   20  of children’s literature(文学) were in fact written for   21 . “Alice in wonderland” is perhaps the most obvious of this.
Children, left for themselves, often   22  the worst possible interest in literature. Just leave a child in a bookshop or a   23   and he will more willingly choose the books written in an imaginative way, or have a look at most children’s comics(连环画), full of the stories and jokes which are the objections of teachers and right-thinking parents.
Perhaps we parents should stop   24  to brainwash children into accepting our taste in literature. After all children and adults are so   25  that we parents should not expect that they will enjoy the same books. So I suppose we’ll just have to compromise（妥协） over the bedtime story.

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单项选择题

核电厂的在役检查可以选择“均匀分布”或“非均匀分布”的检验进度，在核电厂运行寿期的最初（）年，检验进度可以由一种改为另一种。

A、3

B、5

C、8

D、10

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