Abstract
A new chromogen, thiophene-2-hydrazide, for the determination of trace amounts of vanadium in aqueous solution has been developed. The intense yellow, water-soluble, stable and binary complex, formed in acidic medium, is suitable for the determination of 0.5-5 p.p.m. of vanadium ion, with a molar absorptivity of 12.1 × 10
3
mol
-1
cm
-1
, at 410 nm, relative error -0.6 to +4.0% and relative standard deviation 0.3-0.8%, depending on the concentration level of the determinant. Moreover, the colour formation is very fast. Interferences due to foreign ions have been examined.