The Relative Surface Tension of Potassium Chloride Solutions by a Differential Bubble Pressure Method¹

Abstract

Two pairs of conjugate solutions in the binodal area, not saturated with solid sodium nitrate, were determined by direct and complete analysis of the equilibrium phases formed from known mixtures of the three components (complexes 11 and 12 of Table I). The two tie-lines so obtained are sufficient to indicate that the plait point of the binodal curve must lie considerably over toward the dioxane-rich side. Two other points on the binodal curve (numbers 10 and 13 of Table I)were determined synthetically by a kind of titration: addition of solid sodium nitrate, in successive small portions, with shaking, to known weights of suitable mixtures of water and dioxane. The

Interfacial tension of electrolyte solutions

“…It has been noted that the OS theory gives a fairly good quantitative description for concentrations up to 0.1M, above which it consistently underestimates the increase in the interfacial tension [2,3,4,5]. The canonical calculation presented above extends the range of agreement between theory and experiment.…”

“…Appealing to the Gibbs adsorption isotherm [8], it is evident that the depletion of solute near the interface results in an increase of surface tension. Furthermore, the experimental observation that for small concentrations this increase depends only weakly on the ionic size [1,2,3,4,5], suggest the existence of a universal limiting law, similar to the one obtained by Debye and Hückel for bulk properties of electrolyte solutions [7]. Indeed, the calculation of Onsager and Samaras (OS) seems to confirm such a limiting law [9].…”

Surfactant Impurities Can Explain the Jones-Ray Effect

“…Figure 2 gives the surface tension of potassium chloride as measured by three different groups. 13,16,28 There are qualitative differences between the three measurements which can be adequately reproduced with this model by simply assuming a different Table I.…”

A Practical Device for Surface Tension Measurement in Volatile Fluids

“…The data selected for presentation in these tables represent the outermost range of sample measurements, i.e., the data excluded from this paper had percentage differences from the published value neither greater nor smaller than the data listed in the tables. Long and Nutting (1942) Table 1 are typical results for distilled water near the ice point and at room temperature. Each pressure difference measurement in the tables is an average of at least 10 bubbles, where the bubble intervals were kept constant.…”