Lab Report Mn-Steel

Determination of Manganese in Steel Submitted by - Date of Submission 27. 03. 11 Objectives In steel production aside the branding iron, which is the primary source, some amounts of manganese is use together with carbon. The objective of this experiment is determining the manganese amount in the steel change by using UNICAM UV-VIS Spectrometer. Theory Many molecules absorb ultraviolet or visible light. The absorbance of a radical increases as attenuation of the beam increases.Absorbance is directly proportional to the path length, b, and the concentration, c, of the absorbing species. Beers Law states that A = ebc, where e is a constant of proportionality, called the absorptivity. Different molecules absorb radiation of different wavelengths. An absorption spectrum will show a number of absorption bands corresponding to structural groups within the molecule. In this experiment wavelength range between 400-650nm is used in redact to detect in the visible range. Steel is an alloy p rimarily composed of iron with carbon content between 0. 2% and 1. 7% by weight. 1. 5% manganese is may be used too, to provide additional strength for a modest price increase. Carbon and other elements present as a hardening agent, preventing dislocations in the iron atom crystal lattice from sliding bypast one another. Manganese is essential to iron and steel production by virtue of its sulfur-fixing, deoxidizing, and alloying properties. In order to detect the manganese amount in the compound KIO4 is used to oxidize Mn+2 to Mn +7 since Mn+2 does not absorb in the visible region therefor cannot be spy.Tungsten lamp is used in the experiment to reach the range between 400-650nm. After the beam comes from the tungsten lamp, it passes done the monocromator to reach the wavelength range which was selected to find the maximum wavelength. After the light passes through the monocromator it goes through the cuvette and then the detector. The cuvette is make of quartz in order to pass the visible light whereas a glass cuvette would absorb it. The oxidoreduction Reaction 5 IO4 + 2 Mn2+ + 3 H2O ? 2 MnO4 + 5 IO3- + 6 H+ Reagents KMnO4 KIO4 H3PO4 unfamiliar SolutionDeionized Water Apparatus Pipette Beaker Heater UNICAM UV-VIS Spectrometer Quartz Cuvette Volumetric Flask Calculations burden of KMnO4 0. 09149g Weight of KIO4 0. 40807g emax 525nm Absorbance for the unknown 0,415 pic Conclusion I Qualitative and or Quantitative identification II Error watchword While at the addition step of H3PO4 after 5ml of H3PO4 is pipetted, it was transferred into a volumetric cylinder, and then transferred into the unknown resolvent and the blank solution. thither may have been material loss during the process.Dilution errors may have been done during the dilution process. There may be some personal errors made while weighing the compounds Any scratch, stain or fingerprint left on the cuvette may cause a shift from the accurate wavelength in the detected value. If any bubble s left in the cuvette while the detection is made will as well as cause wrong wavelength value. Reference http//teaching. shu. ac. uk/hwb/chemistry/tutorials/molspec/uvvisab1. htm http//www. kimya. boun. edu. tr/webpages/courses/chem308/Determination%20of%20Manganese%20in%20Steel. pdf