VISOCOLOR® HE Iron • Colorimetric determination of iron • Triazine method: iron(II) ions react with a triazine derivative to form a violet complex. • Iron(III) ions are reduced and thus also determined. • Type: high sensitive test kit • Range: 0.0 · 0.01 · 0.02 · 0.03 · 0.04 · 0.05 · 0.07 · 0.10 · 0.15 · 0.20 mg/l Fe • Sufficient for: 300 determinations • Shelf life at least: 24 months • Sea water suitability: no • Detectable with PF-11 no • Natural waters as well as waste waters often contain some iron. • It can be present as Fe(II) or Fe(III) ions if the pH value of the water is below 3 or if the water is free of oxygen. • At higher pH values Fe(III) forms an insoluble oxyhydrate. • Frequently the sample is in a transition state with finely dispersed iron oxides. • In waste water and natural water containing humic acids iron is often present in the form of a complex salt. • The VISOCOLOR® test kits only determine iron which is present in dissolved form as Fe2+ or Fe3+ ions. • Iron complexes are not covered unless they are decomposed by oxidation with nitric acid and sulphuric acid.