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问题 推断题

下列用字母表示的10种物质是由H、C、O、Ca、Cl、Fe中的几种元素组成，它们是初中化学常见的物质．题中“→”表示物质间存在转化关系，部分反应物、生成物及反应条件已略去。已知圈Ⅰ中的转化均是分解反应，圈Ⅱ中的转化均是化合反应。

    

（1）Y是大理石的主要成分，则Y的化学式为           。

（2）N和F是常见的非金属单质，化合物A和B的元素种类相同，化合物D和E的元素种类也相同，请写出A→B反应的化学方程式                                                       ，E+N反应的化学方程式                                                              。

（3）从上述物质中任选物质，按下图所示装置进行实验。当胶头滴管中的液体滴入瓶中，U型管中的液面发生了明显变化，请分别写出符合下列实验现象的物质的化学式。

            现象

序号

a处水液降低b处液面降低
①  
②  
 

答案

（1）CaCO3 （2）2H2O22H2O+O2↑；2CO+O22CO2（3）

            现象

序号

a处水液降低b处液面降低
①HCl   FeCO2   H2O
②CaCO3    HClCO2   Ca(OH)2
 

题目分析：（1）Y是大理石的主要成分，所以Y就是碳酸钙，故答案为：CaCO3；

（2）物质是由H、C、O、Ca、Cl、Fe中的几种元素组成，化合物A和B的元素种类相同，A和B都会转化成非金属单质Y，所以A就是过氧化氢，B就是水，N就是氧气。氧气和F会生成E、D，化合物D和E的元素种类也相同，E和氧气反应会生成D，所以F是碳，E是一氧化碳，D就是二氧化碳，则X就是氢氧化钙，Z是盐酸，M就是金属氧化物，经过验证各物质都满足转换关系。过氧化氢在二氧化锰的催化作用下生成水和氧气，一氧化碳和氧气在点燃的条件下生成二氧化碳，故答案为：2H2O22H2O+O2↑，2CO+O22CO2。

（3）b处液面降低，说明瓶内的压强减小，可以采用气体和液体反应使压强减小，二氧化碳和氢氧化钙，二氧化碳和水都满足要求。a处液面降低，说明瓶内的压强增大，可以采用固体和酸反应生成气体的方法是气压增大，碳酸钙和盐酸反应，铁和盐酸反应。

问答题



1. passage1
The ongoing economic globalization and rapid advances of science and technology have generated unprecedented technological conditions for global economic and social development in the new century. In particular, the development of information and communications technologies has been making tremendous impact on our economic, social and cultural life.
On the one hand, informationization presents valuable "digital opportunities" for economic growth and social progress. On the other hand, it presents various challenges to us. Many countries are taking active measures to push the development of information technologies and the information industry in an effort to accelerate national informatization processes.
However, the development of information industry worldwide is seriously unbalanced. The gap between the rich and the poor in enjoying the benefits of and utilizing information resources and information technologies is widening instead of narrowing, putting the developing countries in a more disadvantageous position. This will inevitably further aggravate the social and economic disparity between the North and the South.
Narrowing and ultimately eliminating the "digital divide" is a major issue to be addressed in the process of building the information society. Otherwise, we could not be able to attain the goal of sustainable, sound and coordinated development of the global information society.
Weak information infrastructure has become a major reason for the gap between developing and developed countries and has seriously impaired the developing countries’ ability to build information society. Therefore, we shall put emphasis on exploring the strategic goals for developing countries to accelerate their information infrastructure build-out.
These strategic goals may include: government macroeconomic control and market regulation policies, information regulation system in line with national conditions, sound relationship between technological development and market growth, avoiding market risks, innovative financing mechanisms for more financing channels, etc.
In the future information society, knowledge and skills will be a major driver for economic growth and one of the major contributors to the sustainable development of the information industry. One of the main reasons for the gap between developing and developed countries in information technologies is the lack of knowledge and human resources, which is a key issue to be considered in bridging the "digital divide".
So we shall consider establishing innovative mechanisms for human resources development and explore ways to improve human resources development on the basis of the existing training centers and training resources as well as the Internet so as to enhance the awareness of information technology.
Moreover, bridging the "digital divide" requires joint efforts of all countries around the world. Developed countries in particular shall truly shoulder their responsibilities in helping the developing countries accelerate their informatization processes and narrowing the "digital divide".
Concrete actions shall be taken, on the basis of the principles of mutually beneficial cooperation, to offer active assistance to developing countries in the form of financial support, technology transfer and human resources training, etc.
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单项选择题

十二经脉的功能活动反映于体表的部位是 ( )

A．奇经

B．经别

C．络脉

D．皮部
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