No abstract

salt (in concentrations below 0.1%) caused low results. This interference was overcome by a large excess of neocuproine. In the case of butyl zymate the color faded rapidly (within 2 to 5 minutes) and no amount of excess neocuproine was of any assistance in overcoming the interference. Barium sulfonate and sodium sulfonate interfered in concentrations above 0.1%. This interference was more of a retarding nature, for after standing for about 4 hours, the color was completely developed. ADVANTAGESThe simplicity of the method described is not only due to the use of neocuproine, but also to the novel approach used in the treatment of the sample. It is thus possible to determine the copper content directly without resorting to any prior treatment of the sample.The advantages may be listed as follows: No ashing or acid extraction No acid dissolution of ash No buffering or chelating No pH adjustments No extraction