问题 选择题

设NA为阿伏加德罗常数的值,下列叙述正确的是 [ ]

A.常温下,1L0.1mol·L-1的NH4NO3溶液中氮原子数为0.2NA

B.1mol羟基中电子数为10NA

C.在反应中,每生成3mol 转移的电子数为6 N

D.常温常压下22.4L乙烯中C-H键数为4 NA 

答案

答案:A

单项选择题
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.

Below are four groups of terms that are found in the passage. Which group contains at least one term that does not refer to the same thing as the other terms within the group

A.the new law, the bill, the drug bill, the prescription-drug legislation, the legislation

B.prescription-drug coverage, the new law, the drug bill, the prescription- drug legislation, the legislation

C.the drug bill, the bill, Medicare with prescription-drug coverage added, the prescription-drug legislation, the legislation

D.the new law, the bill, the drug bill, Medicare with additions including prescription-drug coverage, the prescription-drug legislation