Over a wide range of predictions, they are even closer to 5 % (compare MREs tabulated in Figure ). It is unsurprising to see that relative errors increase with smaller predicted quantities (inset zooms in Figure ) even though absolute errors remain constant. After training, the proposed ffNN shortcut model performs within tolerances of e.g. empirical correlations for physical or thermodynamic properties 1 . 1 The authors acknowledge the vast amount of empirical correlations and do not attempt to extensively assess their accuracy. However, studying reference revealed estimated errors of calculation methods for thermodynamic properties from 1% up to 15% depending on the use case and used equationthis is in line with the presented results. Herein the variable name p denotes pressure, T temperature, x_initial the initial composition of the mixture and x_eq the composition after reaching equilibrium. All these variables can be given as arrays to enable parallel calculation.