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问题 问答题

已知A～N分别代表一种物质，它们之间的转化关系如图所示（部分反应的反应条件和生成物已略去）．A、B、C分别是由短周期元素组成的单质，A是金属，D是无色液体．F是一种离子化含物，其阴阳离子的个数比为1：3，且能与水反应得到两种碱．反应①是实验室检验某离子的方法，反应②是工业、生产N的重要反应．请回答下列问题：

（1）B元素在元素周期表中的位置是______，F的电子式是______．

（2）写出反应①的离子方程式：______

（3）Cu与足量的N的浓溶液反应得到的产物主要是M不是L，其原因是______

（请用上图所示关系中反应的化学方程式回答）．

（4）选择性催化还原（SCR）是在有催化剂的条件下将M转变为无毒的物质，这是目前国外进行尾气治理遍采用的一种方法．亚铬酸铜（Adkin偿化剂）是极好的M催化还原的催化剂，是铜和铬的复合氧化物，成分不固定，如：aCuO•bCr2O3等，统称为亚铬酸铜．

CuNH4（OH）CrO4在295℃分解生成复合的氧化物（催化剂）、氮气及水，写出该反应的化学方程式：______．

（5）已知一定温度（＞100℃）下，反应②的平衡常数为1．将0.8mol K和1.1mol B放入容积为1L的封闭容器中，发生反应②，一段时间后L的浓度为0.4mol/L，此时反应v正______v逆（填“＞”、“＜”或“=”）． 当反应到达平衡后，保持温度不变，再加入一定物质的量的B，重新达到平衡，则L的平衡浓度______（填“增大”、“不变”或“减小”），B的转化率______．（填“升高”、“不变”或“降低”），L的体积分数______（填“增大”、“不变”、“减小”或“无法确定”）．

答案

A是金属，D是无色液体．F是一种离子化含物，其阴阳离子的个数比为1：3，且能与水反应得到两种碱，则A为Na，D为H2O，由K、L、M的转化可知，K为NH3，L为NO，M为NO2，所以B为氧气，E为过氧化钠，G为NaOH，C为氮气，F为Na3N，H为硝酸铵，

（1）B为O，其原子序数为8，位于元素周期表中第二周期第ⅥA族，F为Na3N，其电子式为

，

故答案为：第二周期第ⅥA族；

；

（2）反应为铵盐与碱的反应，该反应的离子反应为NH4++OH-

  △  
.
 
NH3↑+H2O，故答案为：NH4++OH-
  △  
.
 
NH3↑+H2O；

（3）Cu与足量的N的浓溶液反应得到的产物主要是NO2，NO能被浓硝酸氧化，反应为NO+2HNO3（浓）═3NO2+H2O，故答案为：NO+2HNO3（浓）═3NO2+H2O；

（4）反应物为CuNH4（OH）CrO4，生成物为复合的氧化物（催化剂）、氮气及水，该反应的反应方程式为2CuNH4（OH）CrO4

  △  
.
 
2CuO．Cr2O3+N2↑+5H2O，

故答案为：2CuNH4（OH）CrO4

  △  
.
 
2CuO．Cr2O3+N2↑+5H2O；

（5）4NH3+5O2

催化剂
△
4NO+6H2O

开始0.8    1.1      0    0

转化0.4    0.5     0.4   0.6

某时刻0.4   0.6     0.4  0.6

Q=

(0.4)4×(0.6)6
(0.4)4×(0.6)5
＜1=K，则化学反应向正反应方向进行，所以v正＞v逆，

当反应到达平衡后，保持温度不变，再加入一定物质的量的B，平衡正向移动，则L的平衡浓度增大，但B的转化率降低，因L增大的量与总体积的变化的关系不确定，则L的体积分数无法确定，

故答案为：＞；增大；降低；无法确定．

阅读理解

阅读理解。

    A "lost tribe" that reached America from Australia may have been the first Native

Americans, according to a new theory.

    If proved by DNA evidence, the theory will break long established beliefs about the

southerly migration of people who entered America across the Bering Strait, found it

empty and occupied it.

    On this theory rests the belief of Native Americans to have been the first true

Americans. They would be classified to the ranks of escapee, beaten to the New World by

Aboriginals (土著人) in boats.

    To a European, this may seem like an academic argument, but to Americans it is a

philosophical question about identity, Silvia Gonzales, of Liverpool University said.

    Her claims are based on skeletons found in the California Peninsula of Mexico that

have skulls quite unlike the broad Mongolian features of Native Americans. These narrow-

skulled people have more in common with southern Asians, Aboriginal Australians and people

of the South Pacific Region.

    The bones, stored at the National Museum of Anthropology (人类学) in Mexico City,

have been carbon-dated and one is 12,700 years old, which places it several thousand

years before the arrival of people from the North. "We think there were several migration

waves into the Americas at different times by different human groups," Dr. Gonzales said.

"The timing, route and point of origin of the first colonization of the Americas remains

a most contentious topic in human evolution."

    But comparisons based on skull shape are not considered conclusive by anthropologists,

so a team of Mexican and British scientists, backed by the Natural Environment Research

Council, has also attempted to take out DNA from the bones. Dr. Gonzales declined yesterday

to say exactly what the results were, as they need to be checked, but indicated that they

were consistent (一致) with an Australian origin.

1. It is generally considered that the first Native Americans came from ______. [ ]

A. North Asia

B. Australia

C. South Pacific

D. South Asia

2. The skeletons found in the California Peninsula of Mexico have ______. [ ]

A. the broad skull shape

B. the narrow skull shape

C. different features of Aboriginal Australians

D. the same features of Native Americans

3. The underlined "contentious" is similar in meaning to "______". [ ]

A. likely to cause great interest

B. difficult to solve

C. well-known to all

D. likely to cause argument

4. Which of the following statements is true according to the text? [ ]

A. Research on skulls can draw an exact conclusion.

B. DNA tests have proved the fact that the first Native Americans came from Australian.

C. Scientists are still not sure about the origin of the Native Americans.

D. People began to enter America across the Bering Strait about 12,700 years ago.

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单项选择题 A1/A2型题

某男，30岁，发热一周入院。入院次日热势转剧（体温39.5℃），伴白睛黄染，身黄，尿黄，第3日见壮热烦渴，身目黄色如金，烦躁不安，舌红绛，苔黄干，脉洪大，应辨证为（）

A.黄疸胆腑郁热型

B.黄疸湿热兼表型

C.黄疸湿重于热型

D.黄疸疫毒发黄型

E.黄疸热重于湿型
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