除去下列各物质中的少量杂质,所用方法不可行的是 选项物质杂质

除去下列各物质中的少量杂质,所用方法不可行的是

选项

物质

杂质

除去杂质的方法

A

Cu

Fe

用磁铁吸出

B

NaCl

泥沙

加水溶解、过滤、蒸发

C

NaOH

Na2CO3

滴入足量稀盐酸至不再产生气泡

D

O2

水蒸气

通过盛有浓硫酸的洗气瓶

答案

C

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