试题与答案

冷原子吸收法测汞中,KMn04的作用是()。 A.氧化还原性物质 B.防止重金属沉淀

题型:单项选择题

题目:

冷原子吸收法测汞中,KMn04的作用是()。

A.氧化还原性物质

B.防止重金属沉淀

C.作为指示剂

D.破坏有机物、把低价汞全部氧化成二价汞离子

答案:

参考答案:D

解析:在硫酸、硝酸介质中,加入高锰酸钾和过硫酸钾消解水样,使水中汞全部转化为二价汞。注意消解介质的种类。

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