Iron Determination by Colorimetric Method Using O-Phenanthroline

Abstract

Fe2+ reaction with 1, 10-Phenanthroline  determined the quantity of soluble iron (II) in the  sample to transform a weakly colored iron into  an intensely colored complex which could be  used in the analysis. The substance absorbed  certain wavelengths when a light from the source  with a certain intensity and frequency range was  passed to this intensely colored complex. The  intensity of a solution's color is proportional to  the absorbing species concentration and the  absorption is proportional to the substance  concentration. A separate concentration of  standards was prepared and absorbance in 511  nm, the largest wavelength, was determined  using Colorimeter. Using the same standard  technique and reagents, a blank and three  unknown samples were also prepared. A  calibration curve was built following Beer's Law.  The iron concentration was verified using the  equation of the calibration curve and the  absorption under the same experimental  conditions of three unknowns.