欲除去下列物质中的少量杂质,所用试剂正确的是           

 欲除去下列物质中的少量杂质,所用试剂正确的是                      

物质

杂质

试剂

A

CO2

HCl气体

NaOH溶液

B

NaCl溶液

Na2CO3

适量稀硫酸

C

NaOH溶液

Ca(OH)2

过量纯碱溶液

D

CaCO3

Na2CO3

答案

D

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