Ultrasonic absorption properties and Kirkwood–Buff integral functions for hydrogen peroxide–water and propanone–water mixtures at 298.2 K

Kirkwood–Buff integral functions for water(1)–propanone(2) binary liquid mixtures have been calculated from their thermodynamic properties and used in highlighting the dependence of sound absorption properties on mole fraction, x2, of the organic liquid component. At low x2, the dependence of the integral function G22 on x2 points to hydrophobic association, but this trend is overwhelmed as x2 increases by a dominant G11 which points to a degree of microheterogeneity of the mixture at 298.2 K and ambient pressure. These trends are compared with the dependence on mole fraction of the integral functions for water(1)–hydrogen peroxide(2) mixtures. In the latter system, the key quantity is G12, consistent with strong intercomponent interactions.