Spectrophotometric determination of total iron with thioglycolic acid

3 Spectrophotometric determination of total iron with thioglycolic acid 

With iron (II)/(III), thioglycolic acid forms a red-purple colour complex which is measured at = -530 nm (8530 nm = 3 763 1 (mol cm)). The 

It is suitable for the determination of total iron in concentrations greater than 0.3 mg/1. 

Treat 43 ml of the sample solution with 0.3 ml of thioglycolic acid in a 30-ml measuring flask. Alkalize the solution by adding ammonia solution drop by drop a red-purple coloration appears. Dilute to the mark with distilled water and measure the extinction of the solution at 330 nm. 

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