Ionic liquids (ILs) are considered as a proper alternative for conventional solvents. However, they have high viscosity that may result in poor transport phenomena behaviors. This problem can be overcome by mixing ILs with less viscous solvents. Furthermore, several IL processes involve molecular solvents as solvents/reactants and products. Hence, appropriate values of physical characteristics of ILs/molecular solvent systems are required to design and optimize corresponding processes. This clearly implies the necessity to develop deterministic tools for forecasting physical properties of ILs/molecular solvents mixtures. In this study, the physical properties (density, refractive index, and viscosity) of 1-alkyl-3-methylimidazolium cation ([C(n)min](+)) based ILs with molecular solvents, at 298.15 K and atmospheric pressure, are estimated using a connectionist tool. The proposed correlation strategy offers a strong model, which relates density, refractive index, and viscosity of the [C(n)min](+) based ILs-molecular solvent ternary mixtures to independent parameters including molecular weight and normal boiling temperature, simultaneously. A proper statistical analysis is performed to assess strength and generalization of the deterministic model. The developed network results in the coefficient of determination (R-2) of 0.9999, 0.9993, and 0.9995 in obtaining density, refractive index, and viscosity, respectively. In addition, the error analysis shows the mean squared error (MSE) of 7.54 x 10(-7), 6.91 x 10(-7), and 1.59 x 10(-1) while determining density, refractive index, and viscosity. A parametric sensitivity analysis is also conducted to evaluate influences of the input variables on the output parameters. This study can be instructive for design and optimization of chemical processes which employ IL/solvent mixtures. (C) 2019 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.