Monolayers between two immiscible liquids for three-component solutions

4 Monolayers between two immiscible liquids for three-component solutions 

On the other hand, if the third solute is not soluble in the sub-phase solvent and if we dissolve the third solute in a solvent and pour it over a high-density sub-phase liquid which is immiscible with the first solvent, then depending on the density differences and molecular interactions, two behaviors can be seen after the evaporation of the upper solvent layer. Either the solute molecules form an insoluble monolayer on the sub-phase solvent where we can use all the insoluble monolayer equations, or the solute material sinks down inside the subphase solvent if the density of the solute is appreciably higher than the subphase density. 

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