下列符号中，对“2” 含义的理解正确的是（）①2O表示2个氧元素②Fe2+表示每个亚铁离子带2个单位正电荷③Cl2表示2个氯原子④表示+2价的钙元素_刷题宝

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下列符号中，对“2” 含义的理解正确的是（     ）
①2O  表示2个氧元素
②Fe²⁺  表示每个亚铁离子带2个单位正电荷
③Cl₂  表示2个氯原子
④表示+2价的钙元素

A：① ②

B：② ③

C：③ ④

D：② ④

上一题下一题 0.0难度选择题更新时间:2015-07-23 08:13:01

答案(点此获取答案解析）

D

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