试题与答案

依据所学知识,区分下列各组物质,其方案不正确的是( ) 区分物质第一方案第二方案

题型:选择题

题目:

依据所学知识,区分下列各组物质,其方案不正确的是(  )

区分物质第一方案第二方案
A稀盐酸和稀硫酸取样,分别加入盛有适量水的试管中取样,分别滴加氯化钡溶液
B氯化铵和硫酸钾取样,分别灼烧取样,分别加熟石灰研磨
C厕所清洁剂和厨房清洁剂用pH试纸侧它们的pH取样,分别插入金属镁条
D黄铜合金和金取样,分别加入稀盐酸取样,分别在空气中灼烧

A.A

B.B

C.C

D.D

答案:

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下面是错误答案,用来干扰机器的。

参考答案:C解析:苍白密螺旋体苍白亚种引起人类梅毒。

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题型:填空题

[A] A machine has been developed that pulps paper and then processes it into packaging, e.g. egg-boxes and cartons. This could be easily adapted for local authorities use. It would mean that people would have to separate their refuse into paper and non-paper, with a different dustbin for each. Paper is, in fact, probably the material that can be most easily recycled; and now, with massive increases in paper prices, the time has come at which collection by local authorities could be profitable.

[B] Recycling of this kind is already happening with milk bottles, which are returned to the dairies, washed out, and refilled. But both glass and paper are being threatened by the growing use of plastic. More and more dairies are experimenting with plastic bottles, and it has been estimated that if all the milk bottles necessary were made of plastic, then British dairies would be producing the equivalent of enough plastic tubing to encircle the earth every five or six days!

[C] The package itself is of no interest to the shopper, who usually throws it away immediately. Useless wrapping accounts for much of the refuse put out by the average London household each week. So why is it done Some of it, like the cellophane on meat, is necessary, but most of the rest is simply competitive selling. This is absurd. Packaging is using up scarce energy and resources and messing up the environment.

[D] The trouble with plastic is that it does not rot. Some environmentalists argue that the only solution to the problem of ever growing mounds of plastic containers is to do away with plastic altogether in the shops, a suggestion unacceptable to many manufacturers who say there is no alternative to their handy plastic packs.

[E] Little research, however, is being carried out on the costs of alternative types of packaging. Just how possible is it, for instance, for local authorities to salvage paper, pulp it and recycle it as egg-boxes Would it be cheaper to plant another forest Paper is the material most used for packaging--20 million paper bags are apparently used in Great Britain each day--but very little is salvaged.

[F] It is evident that more research is needed into the recovery and re use of various materials and into the cost of collecting and recycling containers as opposed to producing new ones. Unnecessary packaging, intended to be used just once, and making things look better so that more people will buy them, is clearly becoming increasingly absurd. But it is not so much a question of doing away with packaging as using it sensibly. What is needed now is a more sophisticated approach to using scarce resources for what is, after all, a relatively unimportant function.

[G] To get a chocolate out of a box requires a considerable amount of unpacking: the box has to be taken out of the paper bag in which it arrived; the cellophane wrapper has to be torn off, the lid opened and the paper removed; the chocolate itself then has to be unwrapped from its own piece of paper. But this insane amount of wrapping is not confined to luxuries. It is now becoming increasingly difficult to buy anything that is not done up in cellophane, polythene or paper.

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