Ternary System

Exercise No. 2 TERNARY SYSTEMS Liezel Angelique L. Sabaupan, Bethel Faith Rezaga, and Bea Eder Date of Performance: July 1, 2013; Date Submitted: July 11, 2013; Lab Section: 1L; Instructor: Prof. Annabelle T. Abrera Abstract Ternary systems are represented in a Gibbs-Roozeboom diagram. Since a three-component system offers four degrees of freedom, temperature and pressure are held constant. A mixture of acetic acid, water and chloroform was studied in this experiment. A binodal curve was constructed by means of applying turbidimetric titration. Acetic acid-water mixture was titrated with chloroform and acetic acid-chloroform was titrated with water. The acetic acid composition was pre-assigned and the composition of each of the component in the mixture was determined and plotted in the diagram. To locate the tie lines, delta point and plait point, certain amount of three components that will fall within the binodal curve was prepared and the conjugate phases of the resulting mixtures were titrated with standardized NaOH. The composition of acetic acid was plotted in the diagram and the three parameters were experimentally determined. The composition in the experimentally determined plait point was 40% acetic acid, 45% chloroform and 15% water. I. Introduction Aside from a binary system, systems can also have three components which are then called a ternary system. By applying Gibbs’ phase rule, a ternary system predicts four degrees of freedom which means it requires 4 dimensions in order to be plotted in a paper. To be able to come up with a two-dimensional plot, two factors should be held constant (Levine, 2002). In this case, the temperature and pressure is to be held constant. By doing this, the resulting plot would be a composition-composition phase diagram. The mole fraction of each of the component are then plotted, two of these are independent mole fractions whereas the other one is a dependent mole fraction (Mortimer, 2008). Shown below is a sample

References: Levine, I.R. 2002. Physical Chemistry, 6th ed. New York: McGraw-Hill. 385-386. Mortimer, R.G. 2008. Physical Chemistry. 3rd ed. San Diego, California: Elsevier Academic Press. 290. Rogers, D.W. 2011. Concise Physical Chemistry. Hoboken, New Jersey: John Wiley and Sons Inc. 138-139.