问题 填空题

某火电厂的脱硫尾气通入饱和K2CO3溶液吸收池后,经分解池制得纯净的CO2,再在合成塔与H2反应生成甲醇。其工艺艺流程示意图如下:

(1)吸收池中饱和K2CO3溶液吸收CO2的离子方程式是                          

(2)流程示意图中循环使用的物质是                        

(3)300℃时,合成塔中的反应为CO2(g)+3H2(g)CH3OH(g)+H2O(g),在密闭条件下,下列示意图能说明反应进行到t1时刻时达到平衡状态的是         (填字母序号)

(4)利用合成塔中失活后的铬锌触媒可制得含有Cl- 和CrO42- 的溶液,其浓度均为0.01mol/L,向该溶液中逐滴加入0.01mol/L的AgNO3溶液时,首先产生沉淀的阴离子是      (已知:Ksp(AgCl)=1.56×10-10,Ksp(Ag2CrO4)=9.0×10-12)

(5)合成塔中失活的铬锌触媒可用于制备锌锰电池。在碱性条件下,该电池的总反应为:Zn(s) +2MnO2(s) +H2O(l) = Zn(OH)2(s) +Mn2O3(s) ,该电池正极的电极反应式是                   。若用电池电解(惰性电极)足量的Mg(NO3)2和NaCl的混合溶液,电解过程中阴极的现象是                            

答案

(1)CO2+CO32-+H2O=2HCO3-

(2)K2CO3

(3)cd

(4)Cl-

(5)2MnO2+2e-+H2O=2OH-+Mn2O3  有无色气体和白色沉淀产生

题目分析:(1)K2CO3溶液的吸收CO2生成KHCO3,将K+删除写成离子方程式。

(2)KHCO3受热分解又得到K2CO3,这是循环物质;

(3)反应达到平衡状态又两个特征:一是v(正)= v(逆);二是各物质组分含量不变。a图像没有说明逆反应的速率,不能确定;b是反应得到平衡的常数K,与反应是否达到平衡无关,与温度有关,b不能判断平衡与否;c中的CH3OH和CO2的物质的量不变,即组分不变,说明得到平衡状态;d是H2的含量分数不变,也是组分恒定,说明得到平衡状态。

(4)0.01mol/L Cl-,开始沉淀时c(Ag+)==1.56×10-8;0.01mol/L CrO42-,开始沉淀时c(Ag+)==3.0×10-5。故Cl-先沉淀。

(5)氧化剂MnO2做正极材料,得电子,生成Mn2O3,注意环境,故生成OH-。电解(惰性电极)足量的Mg(NO3)2和NaCl的混合溶液,根据放电顺序,阳极Cl-放电,阴极水电离的H+放电,产生OH-,与Mg2+结合生成Mg(OH) 2白色沉淀。sp计算及电化学反应原理。

单项选择题
问答题

(46) History tells us that in ancient Babylon, the cradle of our civilization, the people tried to build a tower that would reach to heaven. But the tower became the tower of Babel, according to the Old Testament, when the people were suddenly caused to speak different languages. In modern New York City, a new tower, that of the United Nations Building, thrusts its shining mass skyward. (47) But the realization of the UN’s aspirations—and with it the hopes of the peoples of the world—is threatened by our contemporary Babel: about three thousand different languages are spoken throughout the world today, without counting the various dialects that confound communication between peoples of the same land.

In China, for example, hundreds of different dialects are spoken; people of some villages have trouble passing the time of day with the inhabitants of the next town. In the new African state of Ghana, five million people speak fifty different dialects. In India more than one hundred languages are spoken, of which only fourteen are recognized as official. To add to the confusion, as the old established empires are broken up and new states are formed, new official tongues spring up at an increasing rate.

In a world made smaller by jet travel, man is still isolated from many of his neighbors by the Babel barrier of multiplying languages. Communication is blocked daily in scores of ways. Travelers find it difficult to know the peoples of other nations. Scientists are often unable to read and benefit from the work being carried on by men of science in other countries. (48) The aims of international trade, of world accord, of meetings between nations, are blocked at every turn; the work of scholars, technologists, and humanists is handicapped. Even in the shining new tower of the United Nations in New York, speeches and discussions have to be translated and printed in the five official UN language—English, French, Spanish, Russian and Chinese. Confusion, delay, suspicion, and hard feelings are the products of the diplomatic Babel.

The chances for world unity are lessened if, in the literal sense of the phrase, we do not speak the same language. (49) We stand in dire need of a common tongue, a language that would cross national barriers, one simple enough to be universally learned by travelers, businessmen, government representatives, scholars, and even by children at school.

Of course, this isn’t a new idea. Just as everyone is against sin, so everyone is for a common language that would further communication between nations. (50) What with one thing and another—our natural state of drift as human beings, our rivalries, resentments, and jealousies as nations—we have up until now failed to take any action. I propose that we stop just talking about it, as Mark Twain said of the weather, and do something about it. We must make the concerted, massive effort it takes to reach agreement on the adoption of a single, common auxiliary tongue.

(47) But the realization of the UN’s aspirations—and with it the hopes of the peoples of the world—is threatened by our contemporary Babel: about three thousand different languages are spoken throughout the world today, without counting the various dialects that confound communication between peoples of the same land.