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科学研究小组的同学在用一定浓度的硫酸溶液处理废金属材料(主要是生铁、镀锌铁皮)时,溶液发烫并闻到了刺激性气味,这种反常现象引起了同学们的思考。从组成物质的元素角度分析,他们猜测气体可能是SO2、CO、CO2、H2中的一种或几种。为了确定该气体的成分,他们进行了如下探究。

查阅资料:I.SO2、CO2都能与碱溶液反应生成盐和水,CaSO3难溶于水;

II.SO2能与酸性高锰酸钾溶液反应并使它褪色,上述其它气体不能。

实验探究:

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