This thesis is concerned with the study of two topics those are: First: The study of densities, refractive indices and viscosities for binary mixtures of 2- methoxyethanol (2-ME) + water over the entire mole fraction .range at 298.15, 303.15, 308.15 and 313.15 K. Excess molar volumes VE were calculated from precise density measurements at different temperature;.VE results are negative over the entire range of mole fractions and become less negative as the temperature increases. The minimum lies at a mole fraction of about 0.35 2- methoxyethanel. The excess refractive indices nE were calculated from refractive index of pure component liquids and of binary mixtures. nE are positive over the whole mole fraction range and become more positive as the temperature decrease. The deviation in molar refractivity ΔR were also calculated. ΔR values are negative over the whole mole fraction range thus, parallel to VE result. The viscosity deviation η E and excess molar Gibbs free energy of viscous flow ΔGE where calculated from experimental viscosity measurements at different temperature, ηE and ΔGE data are positive over the whole mole fraction range. The observed results of VE,nE.ΔR ηE and ΔGE are discussed in terms of molecular interactions in these binary mixtures. Generally, molecular interactions dominant these behaviours are of types, disruption and formation intra- and interhydrogen bonding between like and unlike molecules, respectively, dipole-dipole interaction and interstitial accommodation of component into the other. The experimental excess functions, VE,nE,& ΔR,ηE and ΔGE were fitted to the Redlich-Kister polynomial equation to evaluate the adjustable parameters and standard deviation from ideality. Second: The study of densities, and viscosities for tetrabutylammonium iodide (TBAI) solutions in pure 2-methoxyethanol and in mixture of (0.35 mole fraction 2-ME + H2O) at the concentration range {(6.499-0.2166), (3.2921-0.0996)}x 10-2 mole/L respectivily at 298.15 K. The relative viscosities were used to calculate the A and B viscosity coefficients of Jones-Dole equation. The viscosity B-coefficient of TBAI in pure 2-ME is positive (structure maker), while for TBAI in 0.35 mole fraction 2-ME + H2O) is negative (structure breaker). Those data were discussed in term of solutesolvent molecular interaction. The apparent molar volumes, φ, were calculated from precise density measurements of both TBAI solutions at 298.15 K. By plotting of φ, versus /c for TBAI solutions which is used to fined the apparent molar volume at infinite dilution φ. These data were used for discuss the type of TBAI-solvent molecular interactions.