问题 单项选择题

Aspirin is one of the safest and most effective drugs invented by man. The most popular medicine in the world today, it is an effective pain reliever. Its bad effects are relatively mild. It is also cheap.For millions of people suffering from arthritis, it is the only thing that works. Aspirin, in short, is truly the 20th-century wonder drug. It is also the second largest suicide drug and is the leading cause of poisoning among children. It has side effects that, although relatively mild, are largely unrecognized among users.Although aspirin was first sold by a German company in 1899, it has been around much longer than that. Hippocrates, in ancient Greece, understood the medical value of tree barks and leaves which today are known to contain a chemical found in aspirin. During the 19th century, there was a great deal of experimentation in Europe with this chemical, and it led to the introduction of aspirin. By 1915, aspirin tablets were available in the United States.A small quantity of aspirin relieves pain and inflammation. It also reduces fever by affecting some of the body’’s reactions. Aspirin is very irritating to the stomach lining. The best way is to chew the tablets before swallowing them with water, but few people can stand the bitter taste. Some people suggest crushing the tablets in milk or orange juice.

Aspirin was invented in________.

A.the 20th century

B.the 19th century

C.ancient Greece

D.ancient Germany

答案

参考答案:B

解析:细节题型。见文章第三段首句:Although aspirin was first sold by a German company in 1899,it has been around much longer than that.和同段倒数第三句:During the 19th century,there was a great deal of experimentation in Europe with this chemical,and it led to the introduction of aspirin.选项B正确。

实验题

(9分)某同学探究同周期元素性质的递变规律,并讨论影响化学反应速率的因素,选用的试剂如下:镁条、铝条、铝粉、钠、新制的Na2S溶液、新制的氯水、0.5mol/L的盐酸、3mol/L的盐酸、酚酞试液,其设计的实验方案及部分实验现象如下表:

实验步骤实验现象
①将一小块金属钠放入滴有酚酞试液的冷水中钠块浮在水面上,熔化成闪亮的小球,做不定向移动,随之消失,溶液变红色
②将表面积大致相同的镁条和铝条(均已用砂纸打磨过,分别投入足量的相同体积的0.5mol/L的盐酸中镁条剧烈反应,迅速产生大量的无色气体,而铝条反应不十分剧烈,产生无色气体,镁条消失比铝条快
③将新制的氯水滴加到新制的Na2S溶液中 
④将相同质量的镁条(已用砂纸打磨过)和铝粉分别投入到足量的相同体积的0.5mol/L的盐酸和3mol/L的盐酸中剧烈反应产生气体,但铝粉消失比镁条快
 

请回答下列问题:

(1)实验③的现象是         ,该反应的离子方程式为                      

(2)由实验③得出的实验结论是                             

(3)由实验②可得出决定化学反应快慢的主要因素是                   

(4)实验④中,因为铝粉消失所用的时间短,因此,该同学得出结论:铝比镁易失电子,该结论是否正确?            (填是或否)

(5)通过实验④说明要加快化学反应速率可                      

单项选择题