Spectrophotometric Determination of Cr(III) and Pb(II) Using Their Complexes with 5,11,17,23-Tetra[(2-ethyl acetoethoxyphenyl)(azo)phenyl]calix[4]arene

Figure 11

Plot of HPSAM for simultaneous determination of Cr(III) and Pb(II) ion in various mixtures: , , and (constant concentration of Pb(II) ion and various concentration of Cr(III)) and and (constant concentration of Cr(III) ion and various concentration of Pb(II)).