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问题 选择题

能正确表示下列化学反应的离子方程式的是 （    ）

A．实验室用大理石和稀盐酸制取CO2：2H++CO32- = CO2↑+H2O

B．硫酸铜与氢氧化钡溶液反应：Ba2++SO42-= BaSO4 ↓

C．Fe(OH)3与盐酸反应：H++ OH- = H2O

D．Fe2O3溶于稀硫酸： 6H++ Fe2O3 =" 2" Fe 3++3H2O

答案

答案：D

题目分析：碳酸钙不溶于水，不能拆开，A错误；硫酸铜和氢氧化钡生成硫酸钡和氢氧化铜两种沉淀，B错误；氢氧化铁不溶于水，不能拆开，C错误。

点评：书写离子方程式时易溶于水、易电离的物质写成离子形式，难溶的物质、气体、和水等仍用化学式表示。

多项选择题

质量是标的物内在素质和外观形态的综合，一般以（）等体现出来。

A.品种

B.型号

C.轻重

D.规格

E.等级
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阅读理解

阅读短文，然后根据短文内容简要回答下列问题。

    I had a wish to go abroad for a very long time. Finally a good chance came. Now I'm studying in the USA.

My wish comes true but I am not happy here. I want to go back to China because I hate the food in the USA.

People in the USA eat a lot of bread. They also like fast food and fried chicken very much. But I don't like such

food. I like Chinese food. There are many different kinds of food in China. They are all very delicious. So, I

often go to the Chinese restaurants in America. The food there is nice but it is very expensive. The American

people also like Chinese food very much.

1. Is the writer studying in the USA?

                                                                                                      

2. How does the writer feel in the USA?

                                                                                                      

3. Why does the writer want to go back to China? 

                                                                                                      

4. Do Americans like American food or Chinese food?

                                                                                                      

5. There are many different kinds of food in China, aren't there? 

                                                                                                      
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