掌握化学用语是学好化学的关键。下列化学用语与所表述的意义相符

掌握化学用语是学好化学的关键。下列化学用语与所表述的意义相符合的是
A.H2O——1个水分子B.Na(+1)——1个钠离子
C.3Fe3+ ——3个铁原子D.2H ——2个氢元素

答案

A解析:

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