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（8分）（2012•昭通）如图是实验室制取气体时常用的发生装置和收集装置．

（1）写出标有标号a、b的仪器名称：a：　_________　；b　_________　．

（2）实验室用石灰石和稀盐酸制取二氧化碳，则使用的发生装置是　_________　，发生反应的化学方程式为　_________　．

（3）实验室中选择A和E制取和收集氧气，则反应的化学方程式为　_________　，氧气收集完毕后，为了防止水倒吸，正确的操作方法是　_________　．

答案

（1）a、长颈漏斗；b、集气瓶．

（2）B；CaCO3+2HCl═CaCl2+CO2↑+H2O；

（3）2KMnO4K2MnO4+MnO2+O2↑；先撤导管再熄灭酒精灯．

（1）图中所给仪器的名称为：a、长颈漏斗；b、集气瓶．

（2）在实验室中制取气体时选择发生装置的依据为药品的状态和反应条件，根据在实验室中制取二氧化碳常用大理石和稀盐酸反应来制取，化学方程式为：CaCO3+2HCl═CaCl2+CO2↑+H2O；药品的状态为：固体+液体，反应条件为：不需要加热，所以应该选择B装置来制取二氧化碳气体．

（3）根据实验室中选择A和E制取和收集氧气，其中A装置需要加热，故可以选择高锰酸钾来制取，高锰酸钾在加热的条件下可以分解产生二氧化锰、锰酸钾和氧气，该反应的化学方程式为：2KMnO4K2MnO4+MnO2+O2↑；氧气收集完毕后，为了防止水倒吸，正确的操作方法是先撤导管再熄灭酒精灯．

单项选择题

This is offered as a textbook illustration of the principle that voters are far shrewder than most politicians believe. This case study highlighting Washington’’s inability to fool anyone is based on a recent survey of the attitudes of people on Medicare about their new prescription-drug benefit.Last fall, when Congress added prescription-drug coverage to Medicare, the new law was hailed as a political masterpiece. Congressional Democrats, who overwhelmingly opposed the bill, thundered that they, too, were eager to provide a drug benefit under Medicare, but they championed alternative legislation that offered a larger drug subsidy and smaller incentives to health insurers to participate. Liberals such as Sen. Edward Kennedy were confident that the drug bill, with plenty of holes in its benefit formulas, would inevitably be expanded around the time it took effect.Not many in Congress seemed troubled that the federal budget was deep in deficit, the nation was saddled with future expenditures for the Iraq war and virtually no health care expert believed that the legislation would fit into its projected $400-billion-over-10-years cost framework. The new law was a cynical bargain that had more to do with the 2004 election than a rational approach to the prescription-drug needs of the nation’’s elderly.The prescription-drug legislation seems a compromise between competing ideologies inserted into a fixed congressional budget. Put another way, it was sausage-stuffing in the guise of lawmaking. And, what no one anticipated was the reaction of the elderly, a group that votes in disproportionate numbers.

Also found in Paragraph 1, what does "this case study" probably refer to

A．A case study the writer is to talk about.

B．Part of a textbook on politics.

C．What the author is going to write.

D．Washington’s inability to fool anyone.
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在Visual FoxPro的表中，当某记录的备注型或通用型字段非空时，其字段标识首字母将以 【7】 显示。
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