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问题 实验题

（7分） 根据下列实验装置图，回答问题：

A                       B                        C

（1）装置中标“a”的仪器名称是        。

（2）实验室制取二氧化碳常用的药品是        ，应选用的装置是        （填字母序号，下同），选用这种收集方法的原因是        。检验二氧化碳是否收集满的方法是        。

（3）用高锰酸钾制取氧气时，应选用的装置是        ，反应的化学方程式为        。

答案

（1）长颈漏斗       

（2）大理石和稀盐酸      A          二氧化碳密度比空气密度大

将燃着的木条放在集气瓶口，木条熄灭，说明收集满。

（3）B   2KMnO4  △  K2MnO4 + MnO2 + O2↑

题目分析：（1）熟悉常见仪器，了解名称，图中a是长颈漏斗；

（2）实验室常用大理石和稀盐酸反应制取二氧化碳，是固液不加热的反应，且因二氧化碳密度大于空气的密度，并且可溶于水，所以我们选择A作为制取和收集装置；因二氧化碳不可燃，也不支持燃烧，故验满时，可将燃着的木条放在集气瓶口，若木条熄灭，说明收集满。

（3）用高锰酸钾制取氧气需要加热，又氧气不易溶于水，所以我们可选用B装置，化学反应式是2KMnO4  △  K2MnO4 + MnO2 + O2↑

点评：解答本题的关键是要熟记：发生装置的选择要考虑反应物的状态和反应条件，气体收集装置的选择要看收集气体的密度和溶水性。

阅读理解

Have you seen Avatar? It’s a popular 3D movie, and you may have to wear a special pair of glasses – 3D glasses, to see it. The 3D glasses make the images from the movie look as if they are coming straight at you.

3D movies are really exciting to watch. More and more 3D movies are coming to theaters. Some say that 3D TV sets will come into our homes in the near future. 3D technology can make TV and movies more exciting. However, people with eye problems may get headaches if they spend too much time watching 3D movies. Why?

When we look at an object, each eye sees it at a different angle (角度). Our eyes send the two images to our brain, and the brain puts them together. 3D technology uses two film projectors (投影机)。 One projects left-eye-image and the other projects a right-eye-image. 3D glasses allow us to see a different image in each eye. So, when we are watching a 3D movie, our brain can’t put together the images sent to our eyes. The brain needs to work harder at “reading” the images. That makes it easier for people with eye problems to get dizzy (头晕的) or have headaches.

Dr John Hagan, an eye doctor in Kansas City, said if your eyes can’t focus on the same object at once, you will have trouble watching 3D movies.

小题1:What is Avatar?

A．It’s a kind of 3D projector.

B．It’s a kind of 3D TV set.

C．It’s a movie.

D．It’s an animal.小题2:The 3D glasses can make the images from the movie           。

A．look more beautiful than usual

B．look as if they are coming straight at you

C．look as if they are far away from you

D．look more strange than usual小题3:According to the story, people will have         in their homes in the near future.

A．3D computers

B．3D projectors

C．3D phones

D．3D TV sets小题4:When we look at an object,         .

A．each eye sees the object at the same angle

B．each eye sees a different object at the same time

C．our brain puts the two different pictures together

D．there will be two film projectors in our eyes小题5:If you wear a pair of 3D glasses,          .

A．you will see different images in both eyes

B．you will see the same images in both eyes

C．your brain can’t work at all

D．the images can be put together easily by your brain
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问答题

[背景材料]


某市为改善越江交通状况提出以下2个方案。
方案1：在原桥基础上加固、扩建。该方案预计投资40000万元，建成后可通行20年。这期间每年需维护费1000万元。每10年需进行一次大修，每次大修费用为3000万元，运营20年后报废时没有残值。
方案2：拆除原桥，在原址建一座新桥。该方案预计投资120000万元，建成后可通行60年。这期间每年需维护费1500万元。每20年需进行一次大修，每次大修费用是5000万元，运营60年后报废时可回收残值5000万元。
不考虑两方案建设期的差异，基准收益率为6%。
主管部门聘请专家对该桥应具备的功能进行了深入分析，认为应从F1、F2、F3、F4、F5共5个方面对功能进行评价。表3—29是专家采用0～4评分法对5个功能进行评分的部分结果，表3-30是专家对2个方案的5个功能的评分结果。



[问题]


该桥梁未来将通过收取车辆通行费的方式收回投资和维持运营，若预计该桥梁的机动车年通行量不会少于1 500万辆，分别列式计算2个方案每辆机动车的平均最低收费额(计算结果保留2位小数)。
(注：计算所需系数参见表3-31)

表3-31 计算系数

n(年)102030405060
(P/F，6%，n)0.55840.31180.17410.09720.05430.0303
(A/P，6%，n)0.13590.08720.07260.06650.06340.0619

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