Brownian motion in binary aqueous mixtures

Abstract

This paper investigates the effects of viscosity on the diffusion coefficient D and the mean square displacement MSD of a probe particle for different types of binary aqueous mixtures using empirical data of the bulk properties of substances. The mixing of different liquids or the addition of solid particles in a liquid changes the viscosity of the liquid thus affecting the behavior of the Brownian particle. The D and MSD are influenced by the temperature and viscosity of the liquid where the particle is immersed. Also, a non­linear relationship between D and the temperature and concentration of the mixture was observed. The measurement of D of a probe particle can be used in detecting the presence of impurities by comparing its values for pure and unknown liquids.