问题 填空题

化学就在我们身边,与我们的生活息息相关。请回答以下生活中的问题:    

(1)“沙里淘金”说明黄金在自然界中能够以______________ (填“单质”或“化合物”)形式存在。    

(2)葡萄表皮上因喷洒农药二残留,可以用厨房调料_____________洗净。    

(3)日本福岛核电站使用的具有放射性的钚元素(元素符号为 Pu)有三种原子:Pu -238、Pu-239和 Pu-240,它们都属于钚元素的原因是具有____________________。    

A.相同的质子数            

B. 相同的电子数

C. 相同的中子数            

D. 相同的相对原子质量

(4)长期使用的暖水瓶内胆常有一层水垢(主要成分为碳酸钙),可以用稀盐酸除去。请写出反应的化学方程式_____________________________________。

(5)通常所说的煤气中毒是指由__________(填物质化学式)引起的中毒。

答案

(1)单质        

(2)食醋      

(3)A  

(4)CaCO3+2HCl=CaCl2+CO2↑+H2O

(5)CO

选择题
阅读理解

Researchers in over 80 nations are taking part in a project to conduct a decade-long census(统计) of sea life. Scientists presented some of their findings at a recent conference as the project neared its completion.

In deep icy waters under Antarctica, scientists found bulbous tunicates, an underground animal, and many newly-discovered creatures believed to be related to starfish (海星) and other marine(海洋的)creatures.

Elsewhere in the world’s oceans, they have recently discovered many kinds of underwater life forms new to science. It is all part of a research effort called the Census of Marine Life.

“There are about 2,000 scientists worldwide involved,” said Bob Gagosian, President, CEO of the Consortium for Ocean Leadership. Gagosian helps manage the project. “Everywhere they’ve gone they’ve found new things,” he says. “The ocean basically is unexplored from the point of view of marine living things.”

Researchers have placed small markers on hundreds of fish and marine animals to track by satellite their migration(迁移)routes and to discover places where sea life gathers.

According to Ron O’Dor, a senior scientist with the Census of Marine Life, knowledge of life on the ocean floor is especially limited. “90% of all the information we have is from the top hundred meters of the ocean,” O’Dor states.

And he says the sea floor is, on average, at a depth of 4, 000 meters. And so, as some machines dive far below what people have previously seen, scientists are discovering new species of plants, animals and living things.

Since the census project began, more than 5,300 new marine animals have been found. Ocean researchers say they hope to catalogue 230,000 species during the census —which some say is only a small part of all the creatures living in the sea.

小题1:Why do the researchers place small markers on many marine creatures?

A.To catch them.

B.To research them.

C.To kill them.

D.To protect them.小题2:From what Ron O’Dor says, we can conclude that        .

A.human beings only know a little about marine life

B.the oceans don’t need to be further explored

C.he considers exploring the ocean a dangerous thing

D.the marine creatures mainly live on the top of the ocean小题3:What can we learn from the passage?

A.About 2,000 scientists from America are involved in the project.

B.The census of sea life will last for ten years.

C.230,000 new marine animals have been found.

D.The sea floor is at a depth of 400 meters.小题4:Why does the author write the passage?

A.To tell the news that new marine creatures are being discovered

B.To encourage people to find new marine creatures

C.To prove the importance of marine creatures

D.To introduce the newly-discovered creatures.