A comparative study of machine learning models for predicting the state of reactive mixing

•Machine learning (ML) can understand reactive-mixing phenomena.•ML predicts quantities of interest (QoIs) of reactive-mixing phenomena.•20 Machine learning emulators are used to predict reactive-mixing phenomena.•Linear and Bayesian emulators predict QoIs with accuracy <80%.•Ensemble and MLP ML emulators predict QoIs with accuracy >99%.