问题 填空题

将铝丝浸入CuSO4溶液中,静置,观察到的现象是                    。结合现象分析,溶液中减少的离子是        ,增加的离子是         

答案

铝丝上有红色固体生成,溶液颜色变浅(或溶液由蓝色变为无色)Cu2+ Al3+

金属活动性顺序表中铝排在铜的前面,能与硫酸铜溶液反应生成铜和硫酸铝,故现象为:铝丝上有红色固体生成,溶液颜色变浅(或溶液由蓝色变为无色),溶液中的铜离子被铝置换出铜,而铝成为铝离子,故溶液中减少的是铜离子,增加的离子是铝离子.

故答案为:铝丝上有红色固体生成,溶液颜色变浅(或溶液由蓝色变为无色); Cu2+,Al3+

阅读理解

任务型阅读。

     The Spring Festival is a Chinese traditional festival.  Most of families will get together to enjoy the

Spring Festival. Before we are going to have a wonderful Spring F'estival, we always do some

preparations.         

     First, we will buy many Blew Year's goods to spend the new year, such as pork, beef, chicken, duck,

fish, apples, oranges, bananas, etc. It always cost much money to buy the New Year's goods.    

     Second, we will clean our house and other things to make them newer, such as cleaning the windows,

the bedroom, the living room, the floor, the kitchen, the bathroom, etc.    

     Third, we will call our family members to come back home as soon as possible so that we can get

together in New Year, and enjoy the New Year's Eve dinner. The family members always come back

before the New Year's Eve.    

     The last thing to do is to buy some new clothes, new shoes, cut down your hair. After finishing all these preparation, we are going to have a new year.

1.                     is the most important traditional festival in China.  

2. Before this important festival, we should buy                      to spend the New Year.  

3. We always spend                      to buy the New Year's goods.  

4. We Chinese often get together and enjoy                       .                   

5. For children, the parents always buy                      for them.

问答题