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问题 选择题

下列溶液中微粒的物质的量浓度关系正确的是（  ）

A．Ca(ClO)2溶液中：c(Ca2+)>c(ClO－)>c(OH－)>c(H+)

B．等体积、等物质的量浓度的NaX和弱酸HX混合：c(Na+)=c(X－)>c(OH－)=c(H+)

C．常温下，将25mL0.2mol/L的盐酸与100mL0.1mol/L的氨水混合，所得溶液中：

c(Cl－)>c(NH4+)> c(NH3·H2O)>c(OH－)>c(H+)

D．将0.1mol/L的Na2S溶液与0.1mol/L的NaHS溶液等体积混合，所得溶液中：c(S2－)+2c(OH－)=2c(H+)+c(HS－)+3c(H2S)

答案

答案：D

题目分析：A不正确，应该是c(ClO－)>c(Ca2+)>c(OH－)>c(H+)；B不正确，因为溶液不一定呈中性；C不正确，因为氨水过量，溶液显碱性，即氨水的电离程度大于氯化铵的水解程度，所以应该是c(NH4+)>c(Cl－)> c(NH3·H2O)>c(OH－)>c(H+)；根据电荷守恒和物料守恒可知，D正确，答案选D。

点评：在比较溶液中离子浓度大小时，应该注意利用几个守恒，即电荷守恒、物料守恒和质子守恒。

单项选择题

Freudian theory indeed took western 20th-century civilization by storm. How so The answer lies in four factors.
Of Freud’s powers as a writer and advocate of ideas, and as a possessor of an extraordinary ability to weave together medical knowledge, some genuine insights into the human condition and a powerful imagination, there can be no question. He has the narrative skills of a first-rate novelist, and a knack for devising striking ways to describe the psychological phenomena he studies. His marvelous powers of imagination fed on analogy and metaphor, and annexed the austere terminologies of scientific medicine and psychology to them. This gave them authority. His case studies are highly organized narratives constructed from true-life gossip based on voyeurism—irresistible to human curiosity.
The second attraction—that Freud offers each individual a revelation of secrets about himself that he does not himself know—is equally irresistible. The same compound of insecurity and curiosity, anxiety and desire that makes so many resort against their better judgment to fortune-tellers, is at work here; except that here the imprimatur of science makes the proceeding respectable, which is why people will spend far more on their analysts than on their astrologers.
The third attraction is the promised theory of human nature. Religious accounts of fallen man, of humanity as midway between beast and angel, of imperishable souls trapped in disgusting matter and therefore sinful from birth, had lost their grip with many, while at the same time Darwinian views offered no account of why evolution had made man as he is.
In identifying sexual and aggressive impulses as the fundamental human drives, and in specifying their causes, Freud offered an inclusive philosophical psychology. Humans struggle with conceptual bewilderments about themselves and their complex natures; one can see why the appearance of Freud’s magisterial new insights seemed as welcome as rain in drought.
And finally there is the fact that sex lies at. the core of the stow. Freud performed a great service by liberating debate on the matter, but it is questionable whether the importance he assigns it is correct. The hungry always think of food; the fed put eating in its proper place. The accidents of social history are easily mistaken for the essentials of human nature. The surprise is that people do not see how, at most, sex can only be part of a far more complicated story.
From Animism to Zoroastrianism, every view known to man retains at least a few devotees. There might always be Freudians, and there will always be admirers of Freud’s great imaginative and literary powers; these two, as the foregoing remarks suggest, are intimately linked. But as to Freud’s claims upon troth, the judgment of time seems to be running against him.

There is no doubt that ______ .

A．Freudian theory astonished the western world

B．Freud was an outstanding medical expert

C．Freud was a genius as author and ideologue

D．Freud was expert at writing novels at first
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单项选择题

根据《中国农业银行风险水平评价办法》（农银规章〔2011〕62号）的规定，自营不良贷款清收率计算公式中，对不同类别的贷款规定了不同的折算系数，以引导各行重点清收高风险贷款，（）贷款清收额的放大倍数最高。

A.已核销呆账贷款

B.损失类贷款

C.可疑类贷款

D.次级类贷款
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