现有硅酸盐试样1.000g,用重量法测定其中铁及铝时,得到Fe₂O³⁺Al₂O₃沉淀共重

某硅酸盐试样1.000g，用重量法测得Fe₂O₃和Al₂O₃的总量为0.5000g。将沉淀溶解在酸性溶液中，并将Fe³⁺还原为Fe²⁺，然后用0.03000mol/L K₂Cr₂O₇溶液滴定，用去25.00mL。计算试样中FeO和Al₂O₃的质量分数。

A.2.62%

B.2.26%

C.0.62%

D.0.26%

A.0.62%

B.2.26%

C.2.62%

D.0.26%

A.30.65%

B.31%

C.25.22%

D.25%

A.30.65%

B.31%

C.25.22%

D.25%

A.30.65%

B.31%

C.25.22%

D.25%