题干

将可逆反应:2NO2←→2NO+O2在固定容积的密闭容器中进行,达到平衡的标志是(     )

①单位时间内消耗n mol O2的同时,生成2n mol NO2

②单位时间内生成n mol O2的同时,消耗2n mol NO

③用NO2、NO、O2的物质的量浓度变化表示的反应速率的比为2∶2∶1的状态

④混合气体的密度不再改变的状态

⑤混合气体的颜色不再改变的状态

⑥混合气体的平均相对分子质量不再改变的状态

A:①④⑥

B:②③⑤

C:①③④

D:②⑤⑥

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D

同类题3

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