As observed in the figure, the banana-shaped tail of the population distribution predicted by the SurQCT isothermal heat bath simulation agrees very well with the reference QCT result. Also for the recombination cases, the error plot analysis shows that the population distribution error is within 10% in the entire energy state space. The capability to predict dissociating and recombining scenarios has several implications for the Preprint applicability and potential impact of the proposed surrogate. To list a few: • The predicted rate coefficients can be used to study non-equilibrium in hypersonic applications;