The viscosities, ultrasonic velocities, densities, and refractive indices of glycylglycine and MnCl2 in water have been studied at different temperatures and concentrations. Excess thermodynamic parameters such as adiabatic compressibility (beta(ad)), apparent molar volume (Phi(V)), apparent molar compressibility (Phi(K)), intermolecular free length (L-f), specific acoustic impedance (Z), relative association (R-A), and solvation number (S-n) have been calculated. The variations in apparent molar volume were confirmed by Scaled particle theory, and the changes in apparent molar compressibilities were interpreted using the Kirkwood model. The variations in apparent molar volumes were fitted with Masson's equation. The viscosity data have been fitted using the Jones-Dole empirical equation. The molecular relaxation of MnCl2 and glycylglycine in water gives an idea about solute-solute interactions. The interactions also suggest the formation of H-bonding in the system. The structure forming tendency of the solute has also been indicated by the solvation number.