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问题 选择题

关于下列各装置图的叙述中，不正确的是

A．装置①中，d为阳极、c为阴极

B．装置②可用于收集H2、NH3、CO2、Cl2、NO2等气体

C．装置③中X若为四氯化碳，可用于吸收氨气，并防止倒吸

D．装置④可用于干燥、收集氨气，并吸收多余的氨气

答案

答案：A

题目分析：A、根据图片知，电源的正极是a，负极是b，所以电解池的阳极是c，阴极是d，A错误．B、H2、NH3、CO2、Cl2、HCl、NO2等气体和氧气不反应，可以采用排空气法进行收集；H2、NH3的密度小于空气密度，可以采用向下排空气法进行收集，即导气管“短进长出”，CO2、Cl2、HCl、NO2的密度大于空气的密度，可以采用向上排空气法进行收集，即导气管“长进短出”，B正确．C、四氯化碳的密度大于水的密度且和水不互溶，所以四氯化碳和水混合会分层，氨气和氯化氢气体极易溶于水，且不溶于四氯化碳，所以四氯化碳有缓冲作用，可以用此装置吸收NH3或HCl，并可防止倒吸，C正确．D、碱石灰呈碱性所以能干燥碱性气体氨气，氨气的密度小于空气密度且和氧气不反应，可以用向下排空气法收集氨气，氨气极易溶于水，倒置的漏斗有缓冲作用，所以可以用倒置的漏斗吸收氨气，故D正确。故选A．

填空题

Large companies need a way to reach the savings of the public at large. The same problem, on a smaller scale, faces practically every company trying to develop new products and create new jobs. There can be little hope of raising the money needed from friends and people we know, and while banks may agree to provide short-term finance, they are generally unwilling to provide money, for long-term projects. So companies turn to the public’ inviting people to lend them money, or take a share in the business in exchange for a share in future interests. This they do by issuing stocks and shares in the business through the Stock Exchange. By doing so they can put into circulation the savings of single persons and institutions, both at home and abroad.
When the saver needs his money back, he does not have to go to the company with whom he originally placed it. Instead he sells his shares through a stockbroker to some other Saver who is seeking to invest his money.
Many of the services needed both by industry and by each of us are provided by the government or by local organizations. Without hospitals, roads, electricity, telephones and railways, this country could not work. All these require continuous spending on new equipment and new development if they are to serve us properly, requiring more money than’ it is raised through taxes alone. The government, local organizations and nationalized industries therefore frequently need to borrow money to finance: major capital spending, and they, too, come to the Stock Exchange.
There is hardly a man or woman in this country whose standard of living does not depend on the ability of his or her employers to raise money to finance new development. In one way or another his new money must come from the savings of the country; The Stock Exchange exists to provide a channel through which these savings, can reach those who need finance.

All the basic services on which we depend are ______.
A. unable to provide for the needs of the population
B. financed wholly by rates and taxes
C. in constant need of financial support
D. run by the government or local organizations
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（）不能采用风机反转反风。
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