Fig. 3From: Determination of Cu (II) ions using sodium salt of 4-phenylsemicarbazone 1,2-naphthoquinone-4-sulfonic acid in natural and industrial environmentsDetermination of the composition of the complex CuL, c(Cu 2 +)/(c(Cu 2 +) + c(L)), where c(Cu 2 +) is the concentration of copper (II), while (c(Cu 2 +) + c(L) denotes the sum of concentrations of copper (II) ions and ligandBack to article page