酚酞（C20H14O4）是一种常用的化学试剂，下列关于酚酞的说法正确的是_刷题宝

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酚酞（C₂₀H₁₄O₄）是一种常用的化学试剂，下列关于酚酞的说法正确的是（）

A：酚酞由20个碳原子、14个氢原子和4个氧原子构成

B：酚酞中氧元素的质量分数约为20.1%

C：酚酞的相对分子质量为318g

D：酚酞中C、H、O三种元素的质量比为10：7：2

上一题下一题 0.0难度选择题更新时间:2015-08-27 05:40:04

答案(点此获取答案解析）

B

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