问题 推断题

如图是初中化学常见物质间的转化关系,(反应条件和部分产物已略去),其中C为既不溶于水也不溶于酸的白色沉淀,D、E、I均为气体,X为黑色固体,Y为红色固体,请回答下列问题:

(1)物质C的化学式为________.

(2)写出D→E的化学方程式__________________________.

(3)若现象a无明显变化,则A的化学式可能为___________(填一种).若现象a为“产生能使湿润的红色石蕊试纸变蓝色的有刺激性气味的气体”,则A的化学式可能为__________________(填一种).

(4)写出物质E的一种用途_________.

(5)写出上述物质转化过程中属于复分解反应的一个化学方程式____________________.

答案

(1)AgCl;

(2)CO2+C2CO;

(3)Na2CO3;(NH42CO3

(4)冶炼金属;

(5)Na2CO3+2HCl==2NaCl+CO2↑+H2O.

单项选择题
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阅读理解

     As civilization proceeds in the direction of technology, it passes the point of supplying all the basic

essentials of life-food, shelter, clothes and warmth. Then we are faced with a choice between using

technology to provide and fulfill needs which have now been regarded as unnecessary or, on the other

hand, using technology to reduce the number of hours of work which a man must do in order to earn

a given standard of living. In other words, we either raise our standard of living above that necessary

for comfort and happiness or we leave it at this level and work shorter hours.

      I shall take it for granted that mankind has, by that time, chosen the latter alternative. Men will be

working shorter and shorter hours in their paid employment. It follows that the housewife will also

expect to be able to have more leisure in her life without lowering her standard of living. It also follows

that human domestic servants will have completely ceased to exist. Yet the great majority of the

housewives will wish to be relieved completely from the routine operations of the home such as

scrubbing the floors or the bath of the cooker, or washing the clothes or washing up, or dusting or

sweeping, or making beds.

      By far the most logical step to relieve the housewife of routine is to provide a robot which can be

trained to the requirements of a particular home and can be programmed to carry out half a dozen or

more standard operations, when switched by the housewife.

1. As civilization develops in the direction of technology, ________.

A. the basic essentials of life must be supplied

B. it is important to supply the basic essentials of life

C. it is no longer so important as it was in the past to supply all the basic essentials of life

D. it is not necessary to supply the basic essentials of life

2. According to the author, we are faced with________.

A. the choice of providing and fulfilling our needs

B. the choice of using technology

C. the choice of earning a standard of living

D. a choice between using technology to provide and fulfill needs to reduce the number of working hours

3. What alternative will mankind have chosen in future?

A. To leave our standard of living at this level and work shorter hours.

B. To raise our standard of living.

C. To fulfill needs which have been regarded as unnecessary.

D. To lower our standard of living and work shorter hours.

4. Now most housewives wish to________.

A. stop doing their housework

B. do more housework to improve their life

C. get rid of the heavy burden of their housework

D. do only simple and light housework

5. It can be inferred that robots will be invented_________.

A. to take the place of housewives

B. to help manage a family

C. to do the routine of housework instead of human

D. to provide the daily necessities for man