题目内容

A型题 古蔡法检查砷时,加入碘化钾和氯化亚锡的主要作用是

A. 增加AsH3的生成
B. 将As5+还原成As3+
C. 加快氢气的产生
D. 抑制SbH3的生成
E. 将生成的碘还原成碘离子

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