Brooks Micheal BrooksQuantitative AnalysisWei9 November 2010Determination of Fe by UV-Vis SpectrometryIntroduction:A complex of iron (II) is formed with 1,10-phenanthroline, Fe(C12H8N2)32+, and the absorbanceof this colored solution is measured with a spectrophotometer. The spectrum is plotted to determine the absorption maximum. Hydroxylamine (as hydrochloride salt to increase solubility) is added to reduce Fe3+ to Fe2+ and to maintain it in that state.4 Fe3+ + 2NH2OH → 4Fe2+ + N2O + 4H+ + H2OMaterials:•Phenanthroline•Water•Ferrous Ammonia Sulfate•Iron (II)•Sulfuric Acid•Hydroxylammonium Chloride•Sodium Acetate•Unknown•Volumetric FlasksProcedure:1.)Pipet 1.00, 2.00, 5.00, 10.00, and 25.00mL of iron solution into 100mL volumetric flasks.
Brooks 2.)Add 50mL of distilled water into a 100mL volumetric flask.3.)Add the unknown to another volumetric flask.4.)Add 1.0mL Hydroxylammonium chloride and 5.0mL phenanthroline to the volumetric