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问题 选择题

下列各项中括号里的物质是除去杂质所用的药品（适量），其中错误的是（　　）

A．NaCl混有Na2CO3（盐酸）

B．铁粉中混有铜粉（盐酸）

C．H2中混有HCl（NaOH溶液）

D．硫酸亚铁溶液中混有硫酸铜（铁粉）

答案

A、碳酸钠和盐酸反应会生成氯化钠、水和二氧化碳，加热蒸发后只剩下氯化钠，故A错误，

B、盐酸会与铁反应而不与铜反应，混合物中加盐酸，没有除去杂质，除去了主要物质，故B正确，

C、氢氧化钠会将氯化氢吸收，而不会与氢气反应，最后剩下了氢气，故C错误，

D、铁和硫酸铜反应置换出铜，过滤后，就剩下了硫酸亚铁，故D错误，

故选B．

填空题

纳维泵的最大扬程是（）m。
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单项选择题

Like all the huge metropolises of the world, there are lots of diversions both outdoors and indoors in Chicago. The Art Institute of Chicago has one of the world’s (1) art collections, including more French Impressionist paintings than even in the Paris Louvre itself. The Field Museum of Natural History and the Museum of Science and Industry are also great historical and cultural treasure houses to (2) as well as entertain children and adults (3) In the Field Museum one comes (4) a surprisingly big collection of Chinese exhibits from the ancient (5) to the early century. The Sears Tower and the Buckingham Fountain are the pride of the Chicagoans; (6) having 110 storeys is said to be the highest tower in the world and the (7) is the largest fountain in the United States. Lake Michigan is for yachting in summer time, (8) the highlights of Chicago life all the year round are concerts, operas and plays (9) by the city’s orchestra, opera houses and theatres. In summer, especially around the Independence Day, July 4th, many festivals and fairs are given outdoors, which, (10) crowds and crowds of people, with their parades, fireworks, (11) concerts, water-skiing and good foods.

But with all its attractions and beautiful spots Chicago is also a city (12) for crimes. All the dwelling houses are (13) with three doors and visitors have to speak through microphone (14) in the wall to the residents before they can get admitted. In the streets there are white-color telephones. When one finds oneself (15) , he needs only to knock the receiver (16) the hook and the next instant the police will (17) . If one does not drive a car, it may well be dangerous for him or her to go out alone in the evening. At first I did not take this warning seriously. (18) , my two encounters with the Black people (19) dusk in the neighborhood were so unpleasant and frightening that I have (20) shut myself evenings in my room, in almost all studying, imposing a curfew on myself.

3（）

A.alike

B.both

C.like

D.either
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