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问题 选择题

除去下列各物质中混有的少量杂质，所用试剂和操作方法均正确的是（　　）

序号物质杂质所用试剂和操作方法

A

H2HCl通过足量的NaOH溶液，干燥

B

NaNO3溶液Na2SO4加入过量的Ba（OH）2溶液，过滤

C

NaCl固体细沙加入足量水溶解，过滤

D

铁粉Fe2O3加入适量的稀盐酸，过滤

A．A

B．B

C．C

D．D

答案

A、HCl气体可以用足量的NaOH溶液除去，再把氢气干燥即可，故选项正确；

B、Na2SO4与氢氧化钡反应，会生成新的杂质氢氧化钠，故选项错误；

C、氯化钠溶于水，泥沙不溶于水，可以用过滤法，但是过滤之后，还需要蒸发．故选项错误；

D、稀盐酸与铁粉和Fe2O3都反应，故选项错误；

故选A

完形填空

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问答题 简答题

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