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单选题
为制备干燥、纯净的CO2,将大理石和盐酸反应生成的气体先后通过装有下列物质的两个吸收装置,两个装置中应依次装入(  ).
A

无水CaCl2固体、水

B

饱和NaHCO3溶液、浓H2SO4

C

浓H2SO4、饱和Na2CO3溶液

D

饱和Na2CO3溶液、稀H2SO4


参考答案

参考解析
解析:
A项,得到的气体不干燥;B项,通过饱和的碳酸氢钠除去带出来的氯化氢杂质,之后通过浓硫酸干燥气体,达到效果;C项,先通过浓硫酸得不到干燥的二氧化碳气体;D项,通过稀硫酸达不到干燥气体的目的.
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