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问题 选择题

（2011年四川绵阳，9题）生活中下列做法利用了化学反应原理的是（   ）

A．自制简易净水器净化自来水

B．门锁不易打开时灌入铅笔芯粉末

C．用天然气作燃料煮饭

D．用活性炭除去冰箱中的异味

答案

答案：C

A、自制简易净水器净化自来水的过程中没有新物质生成，属于物理变化；

B、门锁不易打开时灌入铅笔芯粉末的过程中没有新物质生成，属于物理变化；

C、天然气燃烧能生成水和二氧化碳，属于化学变化；

D、用活性炭除去冰箱中的异味的过程中没有新物质生成，属于物理变化．

故选C．

完形填空

阅读下列各小题，根据括号内的汉语提示，用句末括号内的英语单词完成句子，并将答案写在答题卡上的相应题号后。

71. The situation of unemployment has not been so serious ___________________________ (所期待的).  (expect)

72. Tom has been playing basketball on the playground, ___________________________ (脸上全是汗水).  (cover)

73. ___________________________ (余下要做的) is an accurate description of the long process of the experiment.  (leave)

74. It’s widely accepted that never in history ___________________________ (有过) a more successful opening ceremony than that of the Beijing Olympics.  (there)

75. During my last trip my cellphone was left in a hotel accidentally, ______________________  (再也找不到) .  (find)

76. He told us that he was very happy ___________________________ (他现在的处境) . (be)

77. Qian Xuesen went to California from 1935 to 1955, ___________________________ (在那时期) he concentrated on the research into jet planes.  (period)

78. I have no idea whether the machine can be used again but it __________________________ (在维修) in the morning.  (repair)

79. Did you know ___________________________ (到底怎么) the nuclear explosion occurred in Japan?  (it)

80. The air hostess required that___________________________ (我们坐着) until the plane had come to a complete stop.  (remain)
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