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一、计算物质中某元素的质量分数例1有一硫化钠、亚硫酸钠、硫酸钠的混合物,经测定含硫25.6%.则此混合物中含氧量为( ) (A)37.5% (B)36.8% (C)37.6% (D)无法计算
I. Calculate the mass fraction of a certain element in the substance Example 1 There is a mixture of sodium sulfide, sodium sulfite, and sodium sulfate, and the sulfur content is determined to be 25.6%. The oxygen content in the mixture is () (A) 37.5% (B) 36.8% (C) 37.6% (D) cannot be calculated