To illustrate this correlation, the FP value was plotted as a function of molar mass (Figure ) and as a function of ln 𝑃 𝑣𝑎𝑝 (Figure ), the two properties with the strongest correlation. In Figure , it's noticeable that FP tends to be higher for mixtures with a higher molar mass. This behavior occurs because heavier molecules are normally less volatile than lighter ones, and less volatile compounds are generally less flammable. Figure shows that the FP decreases almost linearly with the increase of natural logarithmic of vapor pressure. This is also related to the volatility, as compounds with a higher vapor pressure are usually more volatile and, consequently, more flammable. The strong correlation between these two variables was a decisive factor in selecting them as input data for the neural network.