已知元素X、Y的核电荷数分别是a和b，它们的离子Xm+和Yn﹣的核外电子排布相同，则下列关系式正确的是_刷题宝

题干

已知元素X、Y的核电荷数分别是a和b，它们的离子X^m⁺和Yⁿ^﹣的核外电子排布相同，则下列关系式正确的是（）

A：a=b+m+n

B：a=b﹣m+n

C：a=b+m﹣n

D：a=b﹣m﹣n

上一题下一题 0.0难度选择题更新时间:2018-08-01 11:16:44

答案(点此获取答案解析）

A

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补全对话

A. We Chinese usually eat rice dumplings this day.

B. I hate eating rice dumplings.

C. Thank you for your rice dumpling.

D. I don't think so.

E. Would you like to have one?

F. Already?

G. How about you?

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B: It's June 2^nd.

A: ____ Then it's Dragon Boat Festival today, isn't it?

B: Yes. ____

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B: Sure. ____

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