硼氢化钠【化学式(NaBH4)】,是一种安全车载氢源。 (l)硼氢化

硼氢化钠【化学式(NaBH4)】,是一种安全车载氢源。

l)硼氢化钠中NaBH元素的质最比为_______(最简整数比);

2)硼氢化钠中氢元素的化合价为-1价,硼元素的化合价为______

答案

123:11:4;(2+3.

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