Equations of state of different families are shortly described and reviewed. Simple models, such as the cubic equations of state, are considered in their performance to more sophisticated ones. Furthermore, different mixing rules are discussed, including the simple, random, and the complicate density-dependent mixing rules. Attention has been focused on the problem of the parameter estimation in ... [Show full abstract] equations of state: calculations are presented showing how an equation of state can be tuned for representing thermodynamic properties. Limitations of multiproperty and mixture prediction are also put forward.