题干

要学好化学就要学会归纳总结,下表归纳的内容完全正确的是(    )

A

 安全知识

B

 生活知识

瓦斯爆炸由甲烷燃烧引起

可用燃着的酒精灯去点燃另一酒精灯

含有较多钙镁单质的水叫做硬水

蜂窝煤易燃烧是因为与空气的接触面增大

C

 物质的性质与用途

D

 物质分类

 H2作填充气球的气体是因为它的密度小

N2可作保护气是因为它化学性质稳定

 河水属于混合物

干冰属于单质

A:A   

B:B   

C:C   

D:D

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答案(点此获取答案解析)

C

同类题4

阅读理解

    There were smiling children all the way. Clearly they knew at what time the train passed their homes and they made it their business to stand along the railway, wave to complete strangers and cheer them up as they rushed towards Penang. Often whole families stood outside their homes and waved and smiled as if those on the trains were their favorite relatives. This is the simple village people of Malaysia. I was moved.

    I had always traveled to Malaysia by plane or car, so this was the first time I was on a train. I did not particularly relish the long train journey and had brought along a dozen magazines to read and reread. I looked about the train. There was not one familiar face. I sighed and sat down to read my Economics.

    It was not long before the train was across the Causeway and in Malaysia. Johore Baru was just another city like Singapore, so I was tired of looking at the crowds of people as they hurried past. As we went beyond the city, I watched the straight rows of rubber trees and miles and miles of green. Then the first village came into sight. Immediately I came alive; I decided to wave back.

    From then on my journey became interesting. I threw my magazines into the waste basket and decided to join in Malaysian life. Then everything came alive. The mountains seemed to speak to me. Even the trees were smiling. I stared at everything as if I was looking at it for the first time.

    The day passed fast and I even forgot to have my lunch until I felt hungry. I looked at my watch and was surprised that it was 3:00 pm. Soon the train pulled up at Butterworth. I looked at the people all around me. They all looked beautiful. When my uncle arrived with a smile, I threw my arms around him to give him a warm hug (拥抱). I had never done this before. He seemed surprised and then his weather-beaten face warmed up with a huge smile. We walked arm in arm to his car.

    I looked forward to the return journey.