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标准状况下的HCl气体4.48L溶于水形成100ml溶液，然后与足量的铁屑充分反应．计算：

（1）所得盐酸的物质的量浓度；

（2）生成H2的体积；

（3）将生成的FeCl2配成400ml溶液，此溶液中FeCl2的物质的量浓度是多少？

答案

（1）n（HCl）=

4.48L
22.4L/mol
=0.2mol，c（HCl）=
0.2mol
0.1L
=2mol/L，

答：所得盐酸的物质的量浓度为2mol/L；

（2）Fe+2HCl=FeCl2+H2↑

        2mol       22.4L

        0.2mol     V

V=2.24L，

答：生成H2的体积为2.24L；

（3）n（FeCl2）=0.1mol，

c（FeCl2）=

0.1mol
0.4L
=0.25mol/L，

答：溶液中FeCl2的物质的量浓度是0.25 mol/L．

单项选择题

Research on animal intelligence always makes me wonder just how smart humans are. (51) the fruit-fly experiments described in Carl Zimmer’s piece in the Science Times on Tuesday. Fruit flies who were taught to be smarter than the average fruit fly (52) to live shorter lives. This suggests that (53) bulbs burn longer, that there is an advantage in not being too terrifically bright.

Intelligence, it (54) , is a high-priced option. It takes more upkeep, burns more fuel and is slow off the starting line because it depends on learning—a (55) process—instead of instinct. Plenty of other species are able to learn, and one of the things they’ve apparently learned is when to (56) .

Is there an adaptive value to (57) intelligence That’s the question behind this new research. I like it. Instead of casting a wistful glance (58) at all the species we’ve left in the dust I.Q.-wise, it implicitly asks what the real (59) of our own intelligence might be. This is on the mind of every animal I’ve ever met.

Research on animal intelligence also makes me wonder what experiments animals would (60) on humans if they had the chance.

60().

A.deliver 

B.carry 

C.perform 

D.apply
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多项选择题

根据《工业企业厂界环境噪声排放标准》（GB12348-2008），有关工业企业厂界环境噪声的测量结果，说法正确的是（）

A.修正噪声测量值与背景噪声值相差大于10dB（A）时，噪声测量值不做修正

B.噪声测量值与背景噪声值相差在3dB（A）～10dB（A）之间时，噪声测量值与背景噪声值的差值取整后，按要求进行修正

C.噪声测量值与背景噪声值相差小于3dB（A）时，噪声测量值不做修正

D.各个测点的测量结果应单独评价，同一测点每天的测量结果按昼间、夜间进行评价
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