Curvature Dependence of the Surface Tension and the Theory of Solubility

While the theory of the dependence of surface tension on curvature was well formulated in 1950, experimental support for the surface tension of molecular-sized spherical interfaces is extremely sparse. Here, a correlation between the solubility of a solute gas and the surface tension of the solvent liquid is discussed theoretically and the curvature dependence of the surface tension is calculated for C6H6, C6H12, and CCl4. The determined dividing thickness, Z, for CCl4, C6H6, and C6H12 is 4.7, 4.2 and 4.9 Å, respectively. The calculated values of the solubility and the molar heat of solution for various gases He, Ne, H2, O2, N2, Ar, CH4, and Kr shows good agreement with experimental data. The equilibrium radius and the surface tension at that radius are evaluated and tabulated.