称取纯Fe 2 O 3 和Al 2 O 3 混合物0.5622g,在加热状态下通氢气将Fe 2 O 3 还原为Fe,此时Al 2 O 3 不改变。冷却后称量该混合物为0.4582g。计算试样中Fe、Al的质量分数。
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