题干

七种短周期元素在元素周期表中的相对位置如表所示.其中B的最高价氧化物的水化物能与B的气态氢化物反应生成离子化合物,下列说法正确的是(   )


A

B

C


D

E


F

G


A:氧化物对应的水化物的酸性:G一定强于F

B:简单离子的半径:F>G>C>D

C:1mol EC2中含2mol E﹣C键

D:A、G分别与氢元素形成的化合物中,化学键均为极性共价键

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B

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