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常用气体的收集方法

> 依次进行如下操作，①将CO2通入盛有紫色石蕊试液的试管中，②加热试管，③在试管中加入适量的活性炭，溶液颜色变化的顺序是 ( ) A．红色→紫色→无色 B．红色→无色→紫色 C．无色→紫色→红色 D．紫色→红色→无色

问题：

发布时间：2024-09-09

依次进行如下操作，①将CO2通入盛有紫色石蕊试液的试管中，②加热试管，③在试管中加入适量的活性炭，溶液颜色变化的顺序是 ( )

A．红色→紫色→无色 B．红色→无色→紫色

C．无色→紫色→红色 D．紫色→红色→无色

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