【国家标准】 纳米技术　水溶液中铜、锰、铬离子含量的测定　紫外-可见分光光度法

This document specifies methods of the determination of divalent copper ions (Cu2+)，divalent manganese ions (Mn2+)，and hexavalent chromium ions ［Cr(Ⅵ)］ in aqueous solution using an ultraviolet-visible spectrophotometer.
This document is applicable for the determination of divalent copper ions (Cu2+)，divalent manganese ions (Mn2+) and hexavalent chromium ions ［Cr(Ⅵ)］ in aqueous solution. The soil，food or biological samples can also be measured according to this document after proper treatment.
The detection limits of each ion in aqueous solution to be applied to this document are as follows:the content of Cu2+ is not less than 1.00×10-7 mol/L，the content of Mn2+ is not less than 1.00×10-6 mol/L，and the content of Cr(Ⅵ) is not less than 4.00×10-7 mol/L.
The pH ranges of water samples to be applied to this document are as follows:the pH range of aqueous solutions containing Cu2+ is 2-6，the pH range of aqueous solutions containing Mn2+ is 3-7，and the pH range of aqueous s