问题 选择题

海洋是一个巨大的宝藏。下列物质不经过化学变化就能从海水中获得的是(   )

A.单质溴

B.单质镁

C.氯化钠

D.烧碱

答案

:C

题目分析:海水中提取食盐原理是蒸发结晶,不涉及化学变化。故选C。

AB海水中提取溴、镁都是从化合物转化为单质,必然有化学变化。不符合题意。

D、烧碱(氢氧化钠)不从海水里面提取。它是氯碱工业的产品。

点评:了解典型化工生产原理。

单项选择题
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