问题 推断题

氧化二氯是黄棕色具有强烈刺激性的气体。它的熔点-116℃,沸点3.8℃.氧化二氯不稳定,接触一般有机物易爆炸;它易溶于水(1∶100)同时反应生成次氯酸溶液.制备出之后要冷却为固态才便于操作和贮存。制取少量氧化二氯,是用干燥的氧化汞与氯气反应(还生成HgO·HgCl2)。装置如图,铁架台和夹持仪器已略去。              

部分物质的有关物理数据如下:

试回答:

(1)A中盛有深色固体试剂a是__________,分液漏斗中b试剂是 ____________  。

(2)B中盛有液体c是__________,C中的液体d是___________ 。

(3)D中发生化学反应的化学方程式是 _____________ 。

(4)E中的保温瓶中盛有致冷剂,它应是___________ (在干冰、冰水、液态空气、液氨中选择)。在E的内管得到的Cl2O中可能含有的主要杂质是____________。

(5)装置A、B、C间的连接方式与D、E间的连接方式有明显的区别,这区别是__________,用这些不同的连接方式的主要理由是______________ 。

答案

(1)a:MnO2;b:浓HCl

(2)C 饱和NaCl溶液; d浓H2SO4

(3)2HgO+2Cl2==HgO·HgCl2+Cl2

(4)液态空气    ;Cl2  

(5)D、E中无橡胶塞,氧化二氯接触有机物而爆炸。

阅读理解

阅读理解。

      Bargaining is the rule here in Beijing. At least, it is so in most markets and back-street clothes shops.

Bargaining is an art and if you are unfamiliar (不熟悉) with it, we'd like to offer you some advice. The

tips (窍门) here are often used in Beijing but may help you at any place in the world where bargaining is

practiced.

      DO NOT say how much you want to pay for an item (物品) unless it's near the end of the bargaining.

Always try and drop the seller's offering price as much as possible before opening your mouth with a price.

     DO throw out really low prices like 10 RMB with a big smile.

     DO keep smiling from the beginning to the end. The seller usually continues bargaining with a happy

smiling face. Getting angry hardly gets you the price you want. KEEP in mind the price offered by the

seller at the beginning is usually at least 40% over the generally reasonable price. It can be up to 500%

over.

      DO have an idea of what the item costs. You can ask your friends, people in the hotel or others you

know, or look at the list below. This is very general and is based (根据) on a market like Xiu Shui. You

may not be able to get the lowest prices at Xiu Shui, especially on a weekend when there are lots of

tourists around.

1. Who is this passage written for?[ ]

A. Owners of back-street shops.

B. Businessmen in Beijing.

C.Those who are good at bargaining.

D. Those who travel in Beijing.

2. What is the topic the writer is mainly talking about in this passage? [ ]

A. Beijing markets.

B. Bargaining tips.

C. Lowest prices.

D. Sellers' offer.

3. What is the most important thing to do in bargaining with the seller?[ ]

A. Keep smiling.

B. Be patient.

C. Don't get angry.

D. Don't say anything.

4. What is NOT included in the tips often used to bargain in Beijing?[ ]

A. Find out the true price and go to the markets with friends.

B. Don't offer your price until the end of the bargaining with a smile.

C. Drop the seller's offering price four or five times (倍) until he agrees.

D. Don't go to markets at the time when there are too many tourists.

5. Which of the following can help you get an item you want at the lowest price? [ ]

A. Whenever you go shopping,take a price list with you.

B. You can bargain for anything at the price of 10 RMB.

C. The price range (范围) for you to bargain is usually between 40%and 500%.

D. Xiu Shui Market is the biggest shopping center where prices are always reasonable.

单项选择题