Introduction: According to (Khan): A complexometric titration as defined by IUPAC as a volumetric titration in which a soluble complex can be formed by titrating a metal ion with a ligand in a an aqueous solution and a titrant is one of the reagents used in titration. [4]M(H2O)n + L = M(H2O)(n-1)L + H20 [4](Khan): further statements, here L is the ligand that is formed through the complete replacement of water molecules with other ligands may occur until the MLn complex is formed. “n” is the coordination number of the metal ion and represents the maximum number of monodentate ligands that can be bonded to it [8]Figure 1: The hexacyanoferrate (III) iron ion: contains 6 ligands that are bonded to the central metal therefore has a coordination number equal to 6 (n=6¬). (Hussain,2007) [13]A complexometric titration occurs in an aqueous sample to displace the water from the ion. Since the metal ion will be ionized once in solution, empty shells of empty valence are obtained [1]According to (Biesen), in a complexometric titration a coordination covalent bond is formed through the ability of most metal ions to receive pairs of electrons not shared by an anion or molecule. Also, a ligand: which is a molecule that contains a lone pair of electrons and can therefore form a bond with a complex ion or a metal ion. Therefore a ligand determines the concentration of metal ions. [2] Therefore, according to (Hussain, 2007), the maximum amount of ligands that can take part in a titration is known as the Werner number and allows the formation of complexes.[13]A complexometric titration is based on the following equations:Figure 2 : Adapted from (Huss...... middle of paper ......ble from: https://www.bhsu.edu/Portals/91/AnalyticalChemistry/StudyHelp/LectureNotes/Chapter13.pdfComplexometric Titrations [homepage on the Internet]. No date. [cited March 20, 2014]. Available from: http://www.ciens.ucv.ve:8080/generador/sites/martinezma/archivos/EDTA.pdfGusdinar T. COMPLEXOMETRIC TITRATION A method of application of Inorganic Pharmaceutical Analysis [Internet home page] No date [cited March 20, 2014] Available from: http://download.fa.itb.ac.id/filenya/Handout%20Kuliah/Inorganic%20Pharmaceutical%20Analysis%202008. /English%20Version/05.%20COMPLEXOMETRIC%20TITRATION.pdf.EDTA Titrations [Internet homepage No date [cited 24 March 2014] Available from: http://bionmr.unl.edu/courses/chem221/. lessons/chapter-12.ppt. https://encrypted-tbn0.gstatic.com/images?q=tbn:ANd9GcSr8T9O08hjWT4n_LqSRWKxWaoPh8aUOpDzzdys1C3bMGVeAY9o Aooendix aeb