MUTUAL DIFFUSION IN POLAR–NONPOLAR GASES: KRYPTON – SULPHUR DIOXIDE AND KRYPTON – DIETHYL ETHER

Abstract

The interdiffusion coefficients for the gas mixtures of Kr–SO₂ and Kr–(C₂H₅)₂O have been measured in the temperature range 1 to 45 °C by the two-bulb technique of Ney and Armistead using radioactive ⁸⁵Kr as tracer. A scintillation counter has been used for analyzing the concentration of ⁸⁵Kr at different times. A mass correction was applied to get the normal diffusion coefficients for both the systems.The experimental D₁₂ values have been employed to get the unlike interaction parameters on the Lennard-Jones (12:6) potential and compared with those obtained by using the combination rules for a polar–nonpolar system and the force constants of the polar gas from viscosity as well as from second virial data. For interpreting second virial data for polar gases the assumption of an off-center dipole is found to yield better interaction parameters.