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问题 填空题

水是生命之源，是人类非常重要的物质．

（1）能证明水是由H、O两种元素组成的实验是______实验，该实验发生的化学反应方程式为：______．

（2）某研究性学习小组对嘉陵江水质的状况进行相关调查研究．

①为较准确地测定嘉陵江水样品的酸碱度，你建议使用______（填序号）．

A、紫色石蕊试液     B、蓝色石蕊试液     C、无色酚酞试液    D、pH试纸

②若要检验嘉陵江水属于硬水还是软水，可用的物质是______．

③研究报告里提出以下设想，你认为不合理的是______（填序号）

A、禁止沿河工厂将未经处理的污水向河流中直接排放

B、城市生活污水要经净化处理达标后才能排放

C、指导农民科学合理地使用化肥、农药

D、在河流中投入化学试剂使氮、磷、钾转化为不溶物沉降

④为缓解水资源的紧缺状况，结合你的生活实际，写出一点具体的做法：______．

答案

（1）因为电解水能生成氢气和氧气，所以能说明水是由氢氧元素组成的．化学方程式为2H2O

 通电 
.
 
2H2↑+O2↑．

（2）①较准确地测定嘉陵江水样品的酸碱度，使用pH试纸，而紫色石蕊试液、蓝色石蕊试液、无色酚酞试液只能测定水样的酸碱性；

②检验嘉陵江水属于硬水还是软水，可用的物质是肥皂水，泡沫多的是软水，泡沫少的是硬水；

③A、禁止沿河工厂将未经处理的污水向河流中直接排放，可以防止河流污染；

B、城市生活污水要经净化处理达标后才能排放，可以防止河流污染；

C、指导农民科学合理地使用化肥、农药，可以防止河流污染；

D、在河流中投入化学试剂使氮、磷、钾转化为不溶物沉降，容易造成水体富营养化花，污染水资源，故不合理．

④为缓解水资源的紧缺状况，我们可以节约用水例如使用节水龙头，或者用淘米的水浇花．

故答案为：（1）电解水；2H2O

 通电 
.
 
2H2↑+O2↑．

（2）①D；②肥皂水；③D；④使用节水龙头，或者用淘米的水浇花．

阅读理解

There are many kinds of cars in the world. My grandmother thinks that is because cars are like their drivers. She says, “Rich people have expensive cars, big people have large cars, and old people have old cars,” But I don’t agree with her.

My neighbor, Mrs. Hill, is 82 years old. She drives only on Tuesday, and she drives only to the bank. She never drives more than 30 kilometers an hour. Do you think Mrs. Hill has a very old and small car? No! Her car is new. It is very large and it can go 200 kilometers an hour! My friend Mike is an artist. He draws beautiful pictures with a lot of colors. But his car is black! Mrs. Bates has a very old car. It often has engine(发动机) trouble. Does she have that kind of car because she is very poor? No, she has four factories and two million dollars in the bank. My aunt Mary has a car. Every Sunday, she drives to the country with her husband, her three children , her mother and their dog. 

Now you read about my friends and their cars. Do you agree with my grandmother?

小题1:My grandmother thinks________.  

A．big people drive small cars

B．old people drive new car

C．poor people have expensive cars

D．rich people have expensive cars小题2: Mrs. Hill’s car is _______.

A．fast and new

B．fast but old

C．slow and old

D．fast and small小题3:Mrs. Bates may be ________.

A．a worker

B．an artist

C．a boss

D．a bank clerk小题4:What kind of picture does Mike draw? 

A．He often draws pictures with black

B．He often draws very colorful pictures

C．He draws pictures with only a few colors

D．He never draws beautiful pictures小题5:There are _____ people in my aunt’s car on Sunday?          

A．5

B．6

C．7

D．8
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单项选择题

想定作业分为图上作业，沙盘作业和（）

A.理论分析

B.实地作业

C.灭火器的作用
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