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离子共存

> 下列叙述正确的是（　　） A．非金属元素的原子间只能形成共价键 B． 20484 Po和 19484 Po互为同位素，电子数相差10 C．加入铝粉能够产生氢气的溶液中，可能含有Na+、NO3-、Cl-、S2-四种离子 D．除去NaCl固体中混有的MgCl2杂质：加入足量KOH试剂后过滤，然后将滤液加热蒸干

问题：

发布时间：2024-09-13

下列叙述正确的是（　　）

A．非金属元素的原子间只能形成共价键

B．

20484

Po和

19484

Po互为同位素，电子数相差10

C．加入铝粉能够产生氢气的溶液中，可能含有Na⁺、NO₃^-、Cl^-、S^2-四种离子

D．除去NaCl固体中混有的MgCl₂杂质：加入足量KOH试剂后过滤，然后将滤液加热蒸干

参考答案：

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