(Received: January 6, 2003; Accepted for publication: February 17, 2003; Published on Web: April 22, 2003)
Using Microsoft Excel solver, which is an add-in program to solve optimization problems, a pK distribution was estimated. The pK distribution shows the relation between the pK values and concentrations of acids in a sample solution and is applied to analyze a heterogeneous surface. A titration curve was obtained from titration of a citric acid solution with a sodium hydroxide solution. The theoretical equation of the titration curve was converted into a linear equation. The equation was fitted to experimental data by the linear programming method included in Excel solver. The pK distributions estimated by Excel solver and by a specially designed program applying the simplex method are almost equal. This indicates that Excel solver can not only be applied for excellent estimation of pK distribution, but also that all Excel users can easily carry out similar determinations.
Keywords: Excel solver, Linear programming method, Titration curve, pK distribution
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