新装修房室内存在甲醛（CH2O）、苯（C6H6）等有害物质。下列叙述正

新装修房室内存在甲醛（CH2O）、苯（C6H6）等有害物质。下列叙述正确的是

A.甲醛分子中含有水分子 B.甲醛中碳元素质量分数为40%

C.苯中碳元素与氢元素的质量比为1:1 D.甲醛和苯都属于无机化合物

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新装修房室内存在甲醛（CH2O）、苯（C6H6）等有害物质。下列叙述正

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