Research Article

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 3

Absorption spectra of TEAC-Cr(III) complex at 488 nm with the increasing concentration of Cr(III) ion from 0.2 × 10−5 M to 20 × 10−5 M as TEAC blank.