Liquid ethylene-glycol (EG) is best known as anti-freeze protection in cooling/heating systems as well as in de-icing solutions for vehicles and runways of airports. It serves as an ingredient of electrolytic capacitors, printer's inks and is also a raw material for the production of explosives and synthetic waxes. EG is a sweetly tasting odorless liquid and it is toxic if swallowed in large amounts. EG and EG–water mixtures are used as a media with variable viscosity in experimental studies of the solvent dynamics effect on electrochemical reactions. In this thesis the method of Molecular Dynamic (MD) simulations is used to study various mixtures of ethylene glycol and water mixtures (Antifreeze). The simulations are carried out with at least 1000 atoms mostly at 298 K and some other temperatures The pressure and time step is 1.0 atm 0.001 ps respectively. The purpose of these simulations is the study of some important quantities such as density, mean square displacement (MSD), diffusion coefficient, radial distribution function, excess parameters , hydrogen bonds and activation energyof EG-water mixtures with different mole fractions. Firstly, the simulation is performed in the NPT (isobaric-isothermal) ensemble at 298 K using DL_POLY 2.18 during 1 ns (step 1000000) to equilibrated the systems and then in NVE (micro canonical) to obtain the desired quantities. The second part of the thesis is about the calculation of the number of hydrogen bonds in pure water, pure ethanol and EG-water with different mole fractions. As it was observed experimentally the minimum mixture volume and enthalpy occurs at about mole fraction of 0.4 and also the minimum number of hydrogen bonds also belongs to this mole fraction. In this thesis we reached to this conclusion that this minimum of volume and enthalpy at this mole fraction depends on the strength of hydrogen bonds rather than the number of such bonds.
