THE USE OF EXCEL IN PHYSICAL CHEMISTRY SEMINARS

The main inconvenience in using computers in chemical science courses is the necessity to spend considerable time to teach students to use various software. We are convinced that it is possible to use only one sufficiently universal program in most cases. We have chosen the Microsoft EXCEL spreadsheet. A set of problems developed to be used in the Chemistry Department of Moscow State University at seminars in Chemical Thermodynamics, Kinetics, Catalysis and Molecular Modelling are solved by students using a PC. The authors believe that this allows students to better understand the meaning of physico-chemical models which are discussed rather than simply memorizing formulas. Training students to work with EXCEL is rather easy, and provides them with the ability to solve most problems arising during the study of physical chemistry.

Spreadsheets allow students to perform numerical calculations and obtain graphs at the same working screen. Calculations can readily be performed with changes of model parameters. Speedy solution of sophisticated non-linear equations and optimization makes it possible to obtain results for direct and inverse problems similar to those encountered in research. As a result the seminars, where such problems are solved, turn into small research projects. Students have the opportunity to see the use of the textbook formulas, the effects of changes in different model parameters, the relative input of separate members of the analyzed relation, and to evaluate the methods of solving research problems. Using EXCEL it is possible, for example, to prepare tables of experimental data, to carry out calculations and to construct graphs. It is possible to readily perform data processing using statistical calculations on linear, logarithmic, exponential, power and polynomial functions, thus giving an estimation of the reliability of results and calculating the coefficients of the function from experimental data. Complex equations and system of equations can be solved by numerical methods. The ability to consider various physico-chemical equations, to change parameters, to represent data graphically and to carry out mathematical modelling of various processes helps to build the imagination of the students.

The set of problems and exercises includes support for 26 seminars and 6 tests to be taught within 2 semesters and covers the following topics: principal laws of thermodynamics; thermodynamic functions; chemical equilibrium calculation; phase rule; adsorption; statistical thermodynamics; major chemical reaction kinetics; quasi-steady state and quasi-equilibrium; auto catalysis and oscillating reactions; complex reaction's kinetics; kinetic theory of gases; the calculation of rate constants and activation energies; homogeneous, heterogeneous and enzyme catalysis. In both semester students deal with molecular modelling, calculations of molecular properties and potential energy surfaces.