Extractive-spectrophotometric determination of tin as Sn(II)-ferron complex

Summary Tin(II) forms a yellow coloured complex with ferron which can be extracted into tribenzylamine-chloroform solution from dilute hydrochloric acid medium. Tin is determined spectrophotometrically by measuring the absorbance at 390 nm. Beer's law is valid up to 7 g Sn/ml with a sensitivity of 0.02 g Sn/cm². Chromium, manganese, iron, nickel, cobalt, copper, zinc, lead, magnesium, titanium, thorium, uranium and vanadium do not interfere. The method is quite simple and useful; its applicability has been tested by the analysis of synthetic samples and an alloy sample of gun metal.