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总还原度(Cu(Ⅰ)+2Cu(0))可以用过量的碘酸钾氧化法,在Cu(Ⅱ)被草酸盐掩蔽的情况下测定。碘量法测定未反应的碘酸盐,继之在同一溶液以酸和碘化物分解Cu(Ⅱ)-草酸盐络合物之后,碘量滴定法测定全铜。金属铜与Cu(Ⅰ)和Cu(Ⅱ)的氧化物分离,采用氯化铵(钾)-抗坏血酸酸性溶液溶解氧化物的方法。然后,分离的金属铜以碘酸盐法测定。金属铜、氧化亚铜以及氧化铜之和非常接近100%,故本法相当准确。样品不存在氧化铜时,金属铜可以由总还原度与全铜之差计算,金属铜与氧化亚铜的和也接近100%。本法已经用于颜料中铜的三种氧化态的测定。
The total reduction degree (Cu (I) + 2Cu (0)) can be determined by excess potassium iodate oxidation with Cu (II) masked by oxalate. Iodometric method for the determination of unreacted iodate, followed by the same solution of acid and iodide decomposition of Cu (II) - oxalate complex, the iodometric titration of copper. Metallic copper is separated from the oxides of Cu (I) and Cu (II), and the oxide is dissolved in an ammonium chloride (potassium) -ascorbate acid solution. Then, the separated metallic copper is measured by the iodate method. The sum of metallic copper, cuprous oxide and cupric oxide is very close to 100%, so this law is quite accurate. In the absence of copper oxide in the sample, the metallic copper can be calculated from the difference between the total reduction and the total copper, and the sum of the metallic copper and cuprous oxide is also close to 100%. This method has been used for the determination of three oxidation states of copper in pigments.