Investigations were carried out to develop a sensitive and modified method for the determination of micro-amount of tungsten (VI) in presence of other trace elements. The yellow coloured tungsten (VI) Sn(II)-SCN complex formed between tungsten, thiocyanate and stannous chloride in presence of HCl is quantitatively extractable from the aqueous phase into the organic phase containing tricaprylamine (high molecular weight amine). The complex gives maximum absorption at 420 nm, and is stable upto 72 hours. nle system obeys Beer's law in the range 0.1-8.0 mg of tungsten in the solution, and the molar absorptivity at 420 nm is 7.8 x 10 (-1) mol(-1) cm(-1). The extractability of the complex into tricaprylamine suggests that the coloured species is anionic in nature. Most of the common cations and anions do not interfere.


K KHAN ,M MUMTAZ ,M AMIN ,