In evaluating the emissions of volatile and semi-volatile chemicals from mixtures, Raoult’s Law (or Rule, since it so seldom hold true in the real vs IDEAL world!) is a starting point. The next step is to factor in the chemical activity coefficients, that help account for deviations from ideal behavior. Rather than restate it all here, please check out the discussion in slides 5 to 11 of the linked PDF, “Modeling Phys-Chem Aspects” for an introduction and example. There are links given to two UNIFAC Activity Coefficient calculators.
https://ihmod.org/wp-content/uploads/2023/06/Modeling-Phys-Chem-Aspects-2.pdf