Potentiometric Study of Trismethioninato Complexes of some Essential Transition Metals

Potentiometric study of methionine complexes of chromium, manganese, iron, cobalt and nickel was carried out in aqueous media by titrating with standard sodium hydroxide solution. The values of the stepwise and overall stability constant were obtained by new computational method, ‘ORIGIN 50’. The values of the stepwise stability constants of the complexes were found in general to follow the order K1 > K2 > K3 and that of the overall constants, logβ to be in the range 26.55 – 28.73.