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    精英家教网 > 初中化学 > 题目详情
    “××”牌天然水的部分特征性指标如表所示，表中的“钙、镁、钾”是指（ ）
    A．分子
    B．原子
    C．元素
    D．非金属
    【答案】分析：欲正确解答本题，须知分子、原子、元素和非金属的概念与区别，还要了解表中的“钙、镁、钾”是以什么形式存在．
    解答：解：钙、镁、钾都是以化合物的形式存在于水中，化合物是由元素组成的，故表中的“钙、镁、钾”是指元素．故选C．
    点评：本题主要考查学生对分子、原子、元素和非金属的概念的理解，以及分辨物质存在形式的能力．
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