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(10分)粉末状试样A是由等物质的量的MgO和Fe2O3组成的混合物。进行如下实

题型:填空题

题目:

(10分)粉末状试样A是由等物质的量的MgO和Fe2O3组成的混合物。进行如下实验:

①取适量A进行铝热反应,产物中有单质B生成;

②另取20 g A全部溶于0.15 L 6.0 mol/L盐酸中,得溶液C;

③将①中得到的单质B和溶液C反应,放出1.12 L(标准状况)气体,同时生成溶液D,还残留有固体物质B;

④用KSCN溶液检验时,溶液D不变色。

请回答:

(1)①中引发铝热反应的实验操作是___________,产物中的单质B是_____________。

(2)②中所发生的各反应的化学方程式是_______________________________。

(3)③中所发生的各反应的离子方程式是_______________________________。

(4)若溶液D的体积仍视为0.15 L,则该溶液中c(Mg2+)为________,c(Fe2+)为___________________。

答案:

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