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问题 选择题

某兴趣小组在实验室中模拟炼铁化学原理的实验，对固体产物成分等进行探究。

【设计实验】用一氧化碳还原纯净的氧化铁粉末，实验装置如下图。

【进行实验】该小组按上述实验设计，在一定温度下进行了实验，测得下列数据：

①反应前玻璃管和内盛氧化铁粉末的总质量66．0g（玻璃管的质量为60．0g）

②反应后玻璃管和内盛黑色固体的总质量65．8g（冷却到室温称量）

【分析与讨论】本实验中，玻璃管内固体粉末由红色全部变为黑色。小明同学认为该黑色固体全部是铁，但小华同学提出了质疑，于是大家提出查阅资料。

【查阅资料】①CO还原Fe2O3的固体产物的成分与反应温度、反应时间等因素有关；

②CO还原Fe2O3的实验过程中固体产物可能有Fe3O4、FeO、Fe；

③NaOH溶液与石灰水相似，能吸收CO2，但不变浑。

④

物质性质四氧化三铁氧化亚铁氧化铁铁粉
颜色黑色黑色红色黑色
能否被磁铁吸引能不能不能能
 

【实验与猜想】

（1）该小组同学将反应后的黑色固体研磨后，再用磁铁吸引，发现黑色固体粉末全部能被吸引，则该黑色固体粉末中不可能含有氧化铁和     。

（2）进行猜想：黑色固体粉末可能a．全部为铁、 b．       、c．       。

【得出结论】

（3）通过实验中获得的数据进行计算，得出黑色固体粉末为（写名称）       。

【反思与评价】

（4）一氧化碳还原氧化铁的实验中，若要得到铁可适当提高反应温度。

（5）实验装置图中采用虚线框内的装置，其作用有       。

A．收集CO    B．吸收CO2    C．检验CO2

【实践应用】小明和他的同学想测定某赤铁矿石中Fe2O3的质量分数。用CO与10g赤铁矿石样品充分反应（杂质不参与反应），并将生成的气体用足量的NaOH溶液完全吸收，该溶液总质量与反应时间的变化关系如右图。

（6）上述反应产生CO2的质量为     g；

（7）计算该赤铁矿石中氧化铁的质量分数。     。（需要有计算过程）

答案

(1) 氧化亚铁 ；(2)b. 四氧化三铁 ；c. 铁和四氧化三铁 ；

(3) 四氧化三铁 ；(5)   AB     ；(6)     6.6    g；（7）80%

题目分析：(1)磁铁能吸引铁和四氧化三铁不能吸引氧化铁和氧化亚铁，故该黑色固体粉末中不可能含有氧化铁和氧化亚铁，（2）磁铁能吸引铁和四氧化三铁，所以黑色粉末可能是：a．全部为铁、b. 四氧化三铁、c. 铁和四氧化三铁 ；（3）由实验①②的数据可知黑色固体粉末为四氧化三铁，（5）一氧化碳还原氧化铁时，有多余的一氧化碳排出，一氧化碳是污染空气的气体，实验中药测出二氧化碳的质量故选AB，（6）由图可知氢氧化钠溶液的质量增加6.6g，故二氧化碳的质量为6.6g，

（7）解：设该样品中氧化铁的质量为x

3CO+ Fe2O3  2 Fe +3CO2

160                132

X                  6.6g

x=8.0g

样品中氧化铁的质量分数为：x100%=80%

单项选择题

Passage Three

Uffizi Tries to Outdo Louvre
Uffizi试图胜过卢浮宫
Italy is to try to turn the Uffizi gallery in Florence into Europe’s premier art museum, with an ambitious 56m euro scheme to double its exhibition space.
Giuliano Urbani, Italy’s culture minister, said the enlarged gallery would surpass "even the Louvre".
By the time work is completed, visitors to the extensively remodeled Uffizi will be able to see 800 new works, including many now confined to the gallery’s storerooms for lack of space.
The project—the outcome of nine months of intensive work by a team of architects, engineers and technicians—is a centrepiece of the cultural policy of Silvio Berlusconi’s government.
With refurbishment plans also afoot for the Accademia in Venice and the Brera in Milan, Italy is bent on securing its share of a market for cultural tourism that is threatened not just by the Louvre, but also by the " art triangle" of Madrid, which takes in the Prado, the Thyssen collection and the Reina Sofia museum of art.
Schemes for the expansion of the Uffizi’s exhibition space stretch back almost 60 years. The latest was mooted in the mid-1990s.
But the one adopted by the present Italian government has reached a far more advanced stage than any of its forerunners. Roberto Cecchi, the government official in charge of the project, said yesterday that all that remained to do was to tender for contracts.
The first changes will be seen as early as next week when a collection of pictures by Caravaggio and his school, including the artist’s Bacchus, currently crammed into a tiny room on the second floor, is to be moved to more expansive premises on the first.
Mr.Cecchi said the biggest problem faced by his team was "inserting a museum into a building that is itself a monument". The horseshoe-shaped Palazzo degli Uffizi, began in 1560, was designed by the artist and historian Giorgio Vasari.
The latest plans are bound to stir controversy, involving as they do the creation of new stairwells and lifts in the heart of the building. There has already been an outcry over one proposed element, a seven-storey, canopy-like structure for a new exit by the Japanese architect Arata lsozaki.
But Mr.Urbani said in Florence on Tuesday that part of the scheme was "subject to further evaluation".
At the heart of the plan is the opening up of the first floor of the vast building, which for decades was occupied by the local branch of the national archives.
This will allow visitors to follow a more extensive, and ordered, itinerary that would turn the Uffizi into what Antonio Paolucci, Tuscany’s top art official, called "a textbook of art history".
As at present, visitors will be channelled to the second floor, where they will be able to study early works by Cimabue and Giotto before moving on to admire the gallery’s extraordinary collection of Renaissance masterpieces, including Botticelli’s Primavera.
But most of what was painted after 1500 is to be moved down a storey to new exhibition space, and on the ground floor there will be a more extensive collection than at present of modern art. The overall increase in exhibition space will be from 6,000sq metres to almost 13,000.
Asked if the expansion might not increase the risk of inducing Stendhal’s syndrome—the disorientation, noted by the French novelist, in those who encounter dozens of Italian Renaissance masterpieces—Mr. Cecchi replied fatalistically, "Yes. It’ll double it".

The fact that a group of architects, engineers and technicians spent nine months on the projec! shows that______.

A．it was a large-scale project involving collaboration of experts from various fields

B．it was completed at amazing speed

C．the government attached great importance to the project

D．the government was following the correct cultural policy
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单项选择题

财务风险属于（）.

A.市场风险

B.个别风险

C.系统性风险

D.商业风险
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