| Abstract: | Polarographic and spectrophotometric studies were carried out on Mo (VI)—gallic acid (G) complexes in aqueous solution of perchlorate media. It was found that the number of waves of Mo (VI) depends on gallic acid concentration as well as on the pH of solution. Only a single well-defined irreversible wave is obtained at pH 8.0 for the reduction of Mo (VI) to Mo (III), proportional to Mo (VI) concentration in presence of 20 mM gallic acid with E1/2=?1.22 V vs SCE. The composition of the formed complexes depends on the pH of solution as revealed from spectrophotometric studies, a 1:1 Mo/G complex is formed at pH 3.0 and 1:2 complex at higher pH′s-NMR study of the isolated 1:2 complex proves that the complexation occurs through—OH groups of gallic acid. |
