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问题 选择题

某盐的混合物中仅含三种离子，其中0.45mol Mg2+，0.3mol Cl-，则SO42-的物质的量为（    ）

A．0.1mol

B．0.3mol

C．0. 5mol

D．0.7mol

答案

答案：B

根据溶液的电中性可知，SO42-的物质的量为（0.45mol×2－0.3mol）÷2＝0.3mol，答案选B。

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多项选择题

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