分析如下残缺的反应：RO3- ++6H+=3R2↑+3H2O。下列叙述正确的是_刷题宝

题干

分析如下残缺的反应：RO₃^- + +6H⁺=3R₂↑

+3H₂O。下列叙述正确的是

A：上式中缺项所填物质在反应中作氧化剂

B：R的原子半径在同周期元素原子中最小

C：R一定是周期表中的第VA族元素

D：RO₃^-中的R元素在所有的反应中只能被还原

上一题下一题 0.0难度选择题更新时间:2018-10-05 08:09:00

答案(点此获取答案解析）

B

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