问题 选择题

关于锂的结构和性质判断错误的是       [ ]

①与水反应比钠剧烈 ②原子半径小于钠 ③在空气中燃烧生成氧化锂      ④它的阳离子最外层电子数与钠的阳离子相同 ⑤它是还原剂      

A、①④         

B、②③      

C、③⑤        

D、只有①

答案

答案:A

阅读理解

阅读理解。

     In 1826, a Frenchman named Niepce needed pictures for his business. But he was not a good artist. So he

invented a very simple camera. He put it in a window of his house and took a picture of his yard. That was the

first photograph.

     The next important date in the history of photography was 1837. That year, Daguerre, another French, took

a picture of his studio. He used a new kind of camera and a different process. In his pictures, you could see

everything very clearly, even the smallest details. This kind of photograph was called a daguerreotype.

     Soon, other people began to use Daguerre's process. Travelers brought back daguerreotypes from all around

the world. People photographed famous buildings, cities and mountains.

     In about 1840, the process was improved. Then photographers could take pictures of people and moving

things. The process was not simple. The photographers had to carry lots of films and processing equipment.

But this did not stop the photographers, especially in the United States. After 1840s daguerreotype artists were

popular in most cities.

     Mathew Brady was a well-known American photographer. He took many pictures of famous people. The

pictures were unusual because they were very life-like and full of personality (个性).

     Brady was also the first person to take pictures of war. His 1862 Civil War pictures showed dead soldiers

and ruined cities. They made the war seem more real and more terrible.

     In the 1880s, new inventions began to change photography. Photographers could buy films readymade in

rolls (卷). So they did not have to make the film themselves. Also, they did not have to process the film

immediately. They could bring it back to their studios and develop it later meaning that they did not have to

carry lots of equipment. And finally, the invention of the small handheld camera made photography less

expensive.

     With the small camera, anyone could be a photographer. People began to use cameras just for fun. They

took pictures of their families, friends and favorite places. They called these pictures "snapshot".

     Photographs became very popular in newspapers in the 1890s. Soon magazines and books also used

documentary photographs. These pictures showed true events and people. They were much more real than

drawing.

     Photography also turned into a form of art by the end of the 19th century. Some photographs were not

just copies of the real world. They showed ideas and feelings, like other art forms.

1. The passage is mainly about _____.

A. the invention of cameras

B. a kind of new art-photography

C. the development of photography

D. the important dates in the history of photography

2. The first pictures of a war were taken by _____.

A. a French photographer in the 1840s

B. an American photographer in the 1860s

C. a German reporter in the 1880s

D. a French artist in the 1890s

3. Photography can also be an art form because artists can _____.

A. take anything they like

B. keep a record of real life

C. take photos of the famous people

D. show ideas and feelings in pictures

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