Empirical method for predicting the enthalpy changes of combustion of amides

The enthalpy change of combustion is one of the basic thermochemical characteristics of an organic compound, indicating the amount of heat produced in the complete combustion of the substance. The enthalpy changes of combustion of many organic compounds have been experimentally determined. Hitherto, the existing empirical approaches have aimed at calculating the combustion enthalpy change of individual classes only, which do not always satisfactorily agree with the experimental results. Therefore, the method of correlation?regression analysis is proposed herein to establish the combustion enthalpy changes of previously unexplored compounds. As is known, a linear relationship between two characteristics is possible only if both of them obey the principle of additivity, i.e., in a homologous series of organic compounds with increasing number of CH2-groups, the value of additive characteristic (for example, the enthalpy change of vaporization) should increase by a certain constant amount. nema