Solubility

solubility

Degree to which a substance dissolves in a solvent to make a solution (usually expressed as grams of solute per litre of solvent). Solubility of one fluid (liquid or gas) in another may be complete (totally miscible; e.g., methanol and water) or partial (oil and water dissolve only slightly). In general, “like dissolves like” (e.g., aromatic hydrocarbons dissolve in each other but not in water). Some separation methods (absorption, extraction) rely on differences in solubility, expressed as the distribution coefficient (ratio of a material's solubilities in two solvents). Generally, solubilities of solids in liquids increase with temperature and those of gases decrease with temperature and increase with pressure. A solution in which no more solute can be dissolved at a given temperature and pressure is said to be saturated (see saturation). See also Joel Hildebrand.

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solubility [‚säl·yə′bil·əd·ē]

(physical chemistry)

The ability of a substance to form a solution with another substance.

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Solubility 

the ability of one substance to combine with another and form a homogeneous, thermodynamically stable system of variable composition made up of two or more components. These systems are formed upon interaction of gases with liquids, liquids with liquids, and other similar combinations. The ratios of the components to one another may be either arbitrary or restricted within certain limits. In the latter case, the solubility is said to be limited.

The solubility of a substance under given conditions is determined from the substance’s concentration in a saturated solution. The solubility of various substances in a specific solvent depends on external conditions, mainly on the temperature and pressure. The effect of pressure on solubility is most pronounced with gases. A change in external conditions affects solubility in accordance with the principle of equilibrium shift (see LECHÂTELiER’S PRINCIPLE). Solubility charts of various substances have been compiled for the most important solvents. Such charts either express solubility as a function of external conditions or simply list the solubility under standard conditions.