Monte Carlo simulations were performed in NVT ensemble. We studied thermodynamic properties of ionic solutions using 2D model of core-softened water with added ions. Structures that form at system equilibrium at different ion to water molecule ratios were observed, as well as effect pressure and temperature have on these structures and other thermodynamic properties of studied system. First basic components of the system are presented, water and its properties, anomalies and models, then constituents, properties and a model for ionic liquids. Model made to represent ionic liquids was written in Fortran programming language and resulting simulation run at various starting parameters. Internal energy, its square and pressure were sampled. Results from Monte Carlo simulation in NVT ensemble were compared at constant number of particles in a volume. Different ratios of ions to water affected internal energy and pressure as well as structures that formed. Internal energy decreases linearly with increasing shares of ions, while pressure decreases linearly at low ion ratios and reaches a limit when approaching pure ionic matter. Heat capacity grows with increasing ion to water ratios. Structures formed at low ion percentage are chains of ions with alternating charges, at around fifty percent ions pores are formed and crystal like ionic substance with cavities when just ions were simulated. Pores and cavities form because number of particles in a volume stays the same, while ions bond with each other much closer compared to water particles. At optimal starting density no cavities would appear.
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