问题 多选题

从海藻灰中可以提取碘的主要反应为:2I-+Cl2=2Cl-+I2,下列说法正确的是(  )

A.I-具有氧化性

B.Cl2是还原剂

C.该反应属于置换反应

D.氯气的氧化性比碘强

答案

A.碘离子化合价处于最低价态,只具有还原性,故A错误;

B.反应中Cl元素化合价降低,Cl2为氧化剂,故B错误;

C.反应是一种单质和一种化合物反应生成另一种单质和化合物的反应,属于置换反应,故C正确;

D.根据氧化剂氧化性大于氧化产物氧化性可知,氯气的氧化性比碘单质强,故D正确.

故选CD.

阅读理解

     Everywhere we look, there is the color.  We see it in the sky and in the sea, There is the color in rocks and in all plants and animals. The color makes our homes and schools pretty. We even see the color in our food. It makes things look good.    

     Everything we see has the color. We see green grass and red apples. How can we see colors? We see colors when light hits our eyes. Dogs and any other animals can't see colors. But bees can. They even see colors we don't see. This helps them find flowers to fly to.    

     We sometimes use the names of colors to say things. People may say "see red "when they are angry.

Or you may say you "feel blue". This means you are sad. We use colors to tell us things, too. Red means to stop. Green means to go.

     Some people can't tell one color from another. They can see yellow and blue. But they can't tell red

from green. We say these people are color blind(色盲).

1. The best title of this passage is _________.        

A. Sky      

B. Sea        

C. Color        

D. Beautiful World

2. The first paragraph tells about _________.      

A. many kinds of color      

B. the function of color

C. the color of the sea        

D. the color of the sky

3. The second paragraph tells about _________.         

A. how everything has colors                  

B. how we see color          

C. why apples are red                        

D. why grass is green  

4. The main idea of the third paragraph is that _________.    

A. we can use the names of colors to say things      

B. why people see colors          

C. why people feel blue                

D. people like the red and blue color

5. The main idea of the last paragraph is _________.        

A. people's colors                            

B. color blindness            

C. people and colors                        

D. red and green colors

单项选择题 A1/A2型题