交警常用装有重铬酸钾(K2Cr2O4)仪器检测司机是否酒后驾车。重铬酸钾

交警常用装有重铬酸钾(K₂Cr₂O₄)仪器检测司机是否酒后驾车。重铬酸钾中铬(Cr)元素的化合价是( )

A．+6

B．+5

C．+4

D．+3

答案

A解析:
略

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交警常用装有重铬酸钾(K2Cr2O4)仪器检测司机是否酒后驾车。重铬酸钾

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