Direct and Second Order Derivative Spectrophotometric Determination of Vanadium (IV)

A new spectrophotometric method has been developed for the determination of vanadium (IV) in aqueous dimethyl formamide using 2-hydroxy-3-methoxy benzaldehyde thiosemicarbazone (HMBATC) as a chromophoric reagent. The vanadium (IV) reacts with HMBATC forming a dark yellowish green colored water soluble complex, [V(IV)–HMBATSC] in the pH range of 4.0–7.0. The yellowish green colored complex shows the absorption maximum at 395 nm. The Beer’s law is obeyed in the range of 0.152 to 1.520 mg ml. The molar absorptivity and Sandell’s sensitivity were 2.49 x 10 lit mol cm and 0.02 mg cm respectively. The interference effect of various foreign ions has been studied. The complex has 1:1 [V(IV)–HMBATSC] stoichiometry with a stability constant of 0.72 x 10. A second order derivative spectroscopic method is also developed for the determination of V(IV), which is more sensitive than the zero order method. The developed method has been employed for the determination of V(IV) in water samples.