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问题 实验题

实验室模拟合成氨和氨催化氧化的流程如下：

已知实验室可用饱和亚硝酸钠(NaNO2)溶液与饱和氯化铵溶液经加热后反应制取氮气。

(1)从下图中选择制取气体的合适装置：氮气__________、氢气_________。

(2)氮气和氢气通过甲装置，甲装置的作用除了将气体混合外，还有_________、_________。

(3)氨合成器出来经冷却的气体连续通入乙装置的水中吸收氨，_________(“会”或“不会”)发生倒吸，原因是____________________________________。

(4)用乙装置吸收一段时间氨后，再通入空气，同时将经加热的铂丝插入乙装置的锥形瓶内，能使铂丝保持红热的原因是___________________________，锥形瓶中还可观察到的现象是____________________________________。

(5)写出乙装置中氨氧化的化学方程式：___________________________。

(6)反应结束后锥形瓶内的溶液中含有H+、OH-、_________、_________离子。

答案

(1)a b    (2)干燥气体 控制氢气和氮气的流速

(3)不会 因为混合气体中含有大量难溶于水的氮气、氢气两种气体

(4)氨的氧化反应是一个放热反应 有红棕色气体产生

(5)4NH3+5O24NO+6H2O

(6)  

(1)制取氮气是液+液气，所选为a，氢气为液+固气，所选为b。(2)甲装置可以控制气体流速，干燥气体，使气体混合均匀。(3)由于混合气体中含有大量难溶于水的氮气、氢气两种气体，所以气体连续通入乙装置不会产生倒吸现象。(4)氨气在红热的铂丝作用下被催化氧化是放热反应，所以铂丝可以保持红热，生成的NO反应生成红棕色的NO2。加入水后发生反应3NO2+H2O====2HNO3+NO，生成的硝酸和过量的氨气反应生成硝酸铵。

选择题

一株植物经受如下处理：把叶片X（见下图）曝露在被放射性同位素所标记的CO2中数小时，然后将组织Ⅲ和Ⅳ分别从茎和根上切下来，叶片Ⅰ和Ⅱ也被切下来。你预期会在哪些组织中测出放射性标记的有机物。

[ ]

A．只有叶片Ⅰ

B．只有叶片Ⅰ和Ⅱ

C．只有Ⅲ和Ⅳ两部分

D．Ⅰ、Ⅱ、Ⅲ、Ⅳ的所有组织中

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单项选择题

Low levels of literacy and numeracy have a damaging impact on almost every aspect of adults, according to a survey published yesterday, which offers (1) of a developing underclass. Tests and (2) with hundreds of people born in a week in 1958 graphically illustrated the (3) of educational underachievement. The effects can be seen in unemployment, family (4) , low incomes, depression and social inactivity.

Those who left school at 16 with poor basic skills had been employed for up to four years less than good readers (5) they reached 37. Professor John Bynner, of City University, who carried the research, said that today’s (6) teenagers would even encounter greater problems because the supply of (7) jobs had shrunk.

Almost one fifth of the 1,700 people interviewed for yesterday’s report had poor literacy and almost half (8) with innumeracy, a proportion (9) other surveys for the Basic Skills Agency. Some could not read a child’s book, and most found difficult (10) written instruction.

Poor readers were twice as likely to be a low wage and four times likely to live in a household where partners worked. Women in this (11) were five times as likely to be (12) depressed, (13) both tended to feel they had no control over their lives, and to trust others (14) .

Those who had low literacy and numeracy were seldom (15) in any community organization and less likely than others to (16) in a general election. There had been no (17) in the literary level of (18) reporting problems.

Alan Wells, the agency’s director, said: “ The results emphasize the dangers of developing an underclass people, who were out of work, (19) depressed and often labeled themselves as (20) . There is a circle of marginalization, with the dice against these people and their families.”

8（）

A.struggled

B.faced

C.encountered

D.confronted
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