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问题 选择题

某化学反应的微观过程如图，则下列说法中，不合理的是

A．甲乙两物质参加反应的质量比是1：2

B．生成物都属于氧化物

C．该反应前后分子的种类发生了改变

D．该反应前后反应物和生成物的质量总和没有改变

答案

答案：A

题目分析：根据反应的微观图，可知这个反应的化学方程式为：CH4 + 2O2点燃 CO2 + 2H2O， A、根据化学方程式甲乙两物质参加反应的质量比=16：64=1：4，错误，B、生成物为CO2和H2O，都属于氧化物，正确，C、化学反应的实质：分子的分化和原子的重新组合，该反应前后分子的种类发生了改变，正确，D、质量守恒定律告诉我们：该反应前后反应物和生成物的质量总和没有改变，正确，故选A

阅读理解

阅读理解，选择正确答案。

Dear Peter,            

      How are you? We go to school five days a week. I have a lot of friends in my school. And one of them

is from Canada. His name is Tom. I am learning English. He often teaches me English after school. He wants 

to learn Chinese from me. So I help him with his Chinese. Sometimes we go out on Sundays. Please write to 

me soon.                                                                                  

                                                                                                                                          Love from

                                                                                                                                                 Harry

1. This is a postcard from __________ to __________.[ ]

A. peter Harry         

B. Harry Peter         

C. Perer Tom

2. Harry goes to school _________ a week.[ ]

A. four hours           

B. four days             

C. five days

3. Tom is from __________.[ ]

A. Japan       

B. England      

C. Canada

4. From the postcard we know Harry is a __________. [ ]

A. teacher               

B. student               

C. doctor

5. What does Harry learn?[ ]

A. English      

B. Chinese      

C. Japanese
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改错题

短文改错。

     I watch TV until nearly 12 o'clock, so I could not go over my lessons.This morning I got

up very late that I had to hurry school without breakfast yet I was late of the first class.When

I entered the classroom, the maths teacher had to stop explaining a important problem, and

all the eyes fixed upon me.My face turned to red.Something even worse happened to me in

the English class.The teacher asked me to recite the text, but I could speak nothing but Sorry,

as I did not spend any time preparing my lessons.The teacher looked at me with his coldly

eyes, I stood at my bench without daring to raise my head.What a terrible day I had! I will

never do anything like this.

_____________________________________________________________________
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