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问题 选择题

下列化学用语正确的是（　　）

A．一氯甲烷的分子式：CH3Cl

B．乙酸的实验式：C2H4O2

C．乙炔的结构简式：CHCH

D．羟基的电子式：

答案

A、分子式是表示物质的组成成分，一氯甲烷的分子式CH3Cl，故A正确；

B、实验式又称最简式，是化学式的一种，用元素符号表示化合物分子中元素的种类和各元素原子个数的最简整数比的式子，则乙酸的实验式为CH2O，C2H4O2为乙酸的分子式，故B错误；

C、乙炔分子的结构简式不能够省略碳碳三键，乙炔的结构简式为CH≡CH，故C错误；

D、氧原子与氢原子通过一对共用电子对连接，羟基是电中性基团，羟基的电子式为，故D错误；

故选A．

选择题
要清楚的反映各国人口占世界总人口的百分比应绘制（　　）
A．扇形统计图B．折线统计图C．条形统计图
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单项选择题

With the spread of inter-active electronic media a man alone in his own home will never have been so well placed to fill the inexplicable mental space between cradle and crematorium. So I suspect that books will be pushed more and more into those moments of travel or difficult defecation (1) people still don’t quite know what to do with.

When people do read, I think they’ll want to feel they are reading literature, or (2) something serious. (3) you’re going to find fewer books presenting themselves as no- nonsense and (4) assuming literary pretensions and being packaged as works of art. We can expect an extraordinary variety of genre, but with an underlying (5) of sentiment and vision.

Translators can only (6) from this desire for the presumably sophisticated. We can look forward to lots of difficult names and fantastic stories of foreign parts enthusiastically (7) by the overall worship of the "global village" Much of this will be awful and some wonderful, (8) don’t expect the press or the organizers of prizes to offer you much help in making the appropriate distinctions. They will be chiefly (9) in creating celebrity, the greatest enemy of discrimination, but a good prop for the (10) consumer.

Every ethnic grouping over the world will have to be seen to have a great writer--a phenomenon that will (11) a new kind of provincialism, more chronological than geographic, (12) only the strictly contemporary is talked about and (13) . Universities, including Cambridge, will include (14) their literature syllabus novels written only last year. (15) occasional exhumation for the Nobel, the achievements of ten or only five years ago will be largely forgotten.

In short, you can’t go too far wrong when predicting more of the same. But there is a (16) side to this--the inevitable reaction against it. The practical things I would like to see happen--publishers seeking less to (17) celebrity through extravagant advertising, (18) and magazines (19) space to reflective pieces--are rather more improbable than the Second Coming (耶稣复临). But dullness never quite darkens the whole planet. In their own idiosyncratic fashion a few writers will (20) be looking for new departures.

4（）

A.fewer

B.more

C.less

D.much
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