Abstract: The problem of calculating the thermodynamic functions of chemical reactions is solved. A database on the
thermodynamic properties of individual substances has been created and programmatically implemented, on the basis of which a
module for calculating the thermodynamic functions of chemical reactions has been developed. The calculation algorithm is based on
the use of Hess' law. Visual Studio 2019 and the C# programming language were chosen as the software product development
environment. An object-oriented approach has been applied and classes for storing thermodynamic parameters of individual
substances have been developed; classes for displaying in graphical and tabular form; class of calculation and verification of
thermodynamic functions. For the convenience of the user's work with chemical reactions, the functions of searching for chemical
reactions by elements and the procedure for saving the reaction to the program database are implemented. An algorithm is
implemented that takes into account the correct balance of chemical elements of the starting substances and reaction products. The
database and the software product can be used for thermodynamic calculations in metallurgy, oil refining, chemical industry, waste
processing and the use of mineral resources. The use of computer programs for thermodynamic calculations will reduce the
calculation time and increase its accuracy by minimizing the human factor.
Index terms: chemical reactions, database, thermodynamics, algorithm, automatic verification.