题干

某研究性学习小组为了探究镁粉与溴水反应的机理,做了如下四种实验:①将镁粉投入到冷水中,未观察到明显现象;②将镁粉投入到溴水中,观察到只是开始时产生极少量的气泡,但溴水会慢慢褪色;③将镁粉投入到液溴中,未观察到明显现象;④向含有足量镁粉的液溴中滴加几滴水,观察到溴的红棕色很快褪去。下列关于镁粉与溴水的反应机理的叙述中正确的是

A:镁粉只直接与溴水中的溴反应

B:镁粉只与溴水中的酸反应

C:产生极少量的气泡是由于镁粉与水反应得到的

D:镁粉在水的催化下与溴发生反应

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答案(点此获取答案解析)

D

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