（2011年山东潍坊，2题）下列变化中，不属于化学变化的是
A．用盐酸除去热水瓶中的水垢
B．铜在潮湿的空气中生成铜锈
C．使用汽油除去衣服上的油污
D．福岛核电站发生氢气爆炸
答案：C
考点：
专题：物质的变化与性质．
分析：化学变化是指有新物质生成的变化，物理变化是指没有新物质生成的变化．化学变化和物理变化的本质区别是否有新物质生成．
解答：A、稀盐酸能和水垢中的碳酸钙反应生成氯化钙、水和二氧化碳，属于化学变化．错误；
B、铜生锈的过程中有新物质--铜锈生成，属于化学变化．错误；
C、油污溶解于汽油的过程中没有新物质生成，属于物理变化．正确；
D、氢气燃烧能生成水，属于化学变化．错误．
故应该选C．
点评：解答本题要分析变化过程中是否有新物质生成，如果没有新物质生成就属于物理变化，如果有新物质生成就属于化学变化．
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