3. Forecasting thermochemical properties in the gas phase

3.1 Thermochemical properties of perfect gases

Many industrial applications in chemical engineering and the energy sector (combustion, thermal machines, etc.) require knowledge of thermodynamic and thermochemical properties such as enthalpies of formation, free enthalpies of formation, absolute entropies and heat capacities of pure substances and mixtures. These properties are generally used to establish energy, entropy or exergy balances for unit operations such as reactors, combustion chambers or heat exchangers. In particular, they are used to evaluate sensible heats, chemical equilibrium constants or reaction enthalpies.

To evaluate the thermochemical properties of fluid phases, it is generally necessary to know the ideal thermochemical properties (perfect...