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问题 选择题

下列关于0.1 mol·L－1CH3COONa溶液的说法正确的是  （  ）

A．加入少量NaOH固体，c(CH3COO－)增大

B．加入少量FeCl3固体，c(CH3COO－)增大

C．稀释溶液，溶液的pH增大

D．加入适量醋酸，得到的酸性混合溶液：c(Na＋)＞c(CH3COO－)

答案

答案：A

题目分析：醋酸钠溶于水，CH3COO－水解，即CH3COO－＋H2OCH3COOH＋OH－。加入少量NaOH固体，抑制CH3COO－水解，c(CH3COO－)增大，A正确；铁离子水解，溶液显酸性，促进CH3COO－水解，c(CH3COO－)降低，B不正确；稀释促进CH3COO－水解，但溶液的碱性降低，即pH降低，C不正确；D中根据电荷守恒c(Na＋)＋c(H＋)＝c(CH3COO－)＋c(OH－)，溶液显酸性，则c(Na＋)＜c(CH3COO－)，D不正确，答案选A。

点评：该题是高考中的常见题型，属于综合性试题的考查，对学生的思维能力提出了较高的要求，本题贴近高考，综合性强，侧重对学生能力的培养，意在培养学生的逻辑推理能力和创新思维能力。该题的关键是在明确反应原理的基础上利用好几种守恒关系，即电荷守恒、物料守恒以及质子守恒，然后结合题意灵活运用即可。

单项选择题 案例分析题

某作者在阅读大量原始文献后，对文献中探讨的产后抑郁症防治和护理干预问题的进展情况进行归纳、总结、对比、分析和评价，加上自己的观点写成一种专题性的学术论文。

一般要求此类论文参考文献中近3年发表过的文献比例应达到（）。

A.40%以上

B.50%以上

C.60%以上

D.70%以上

E.80%以上
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单项选择题

Passage Two

The idea of building "New Towns" to absorb growth is frequently considered a cure-all for urban problems. It is wrongly assumed that if new residents can be diverted from existing centers, the present urban situation at least will get no worse. It is further and equally wrongly assumed that since European New Towns have been financially and socially successful, we can expect the same sorts of results in the United States.
Present planning, thinking, and legislation will not produce the kinds of New Town that have been successful abroad. It will multiply suburbs or encourage developments in areas where land is cheap and construction profitable rather than where New Towns are genuinely needed.
Such ill-considered projects not only will fail to relieve pressures on existing cities but will, in fact, tend to weaken those cities further by drawing away high-income citizens and increasing the concentration of low-income groups that are unable to provide tax income. The remaining taxpayers, accordingly, will face increasing burdens, and industry and commerce will seek escape. Unfortunately, this mechanism is already at work in some metropolitan areas.
The promoters of New Towns so far in the United States have been developers, builders, and financial institutions. The main interest of these promoters is economic gain. Furthermore, federal regulations designed to promote the New Town idea do not consider social needs as the European New Town plans do. In fact, our regulations specify virtually all the ingredients of the typical suburban community, with a bit of political rhetoric (修辞) thrown in.
A workable American New Town formula should be established as firmly here as the national formula was in Britain. All possible social and governmental innovations as well as financial factors should be thoroughly considered and accommodated (容纳) in this policy. Its objectives should be clearly stated, and both incentives and penalties should be provided to ensure that the objectives are pursued. If such a policy is developed, then the New Town approach can play an important role in alleviating America’s urban problems.

According to the writer, the advocators of New Towns in the U. S. ______.

A．mainly have profit in mind

B．attach importance to social needs

C．hope to relieve pressures on existing cities

D．intend to follow the European example
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