<P> Under certain conditions, the equilibrium solubility can be exceeded to give a so - called supersaturated solution, which is metastable . Metastability of crystals can also lead to apparent differences in the amount of a chemical that dissolves depending on its crystalline form or particle size . A supersaturated solution generally crystallises when' seed' crystals are introduced and rapid equilibration occurs . Phenylsalicylate is one such simple observable substance when fully melted and then cooled below its fusion point . </P> <P> Solubility is not to be confused with the ability to' dissolve' a substance, because the solution might also occur because of a chemical reaction . For example, zinc' dissolves' (with effervescence) in hydrochloric acid as a result of a chemical reaction releasing hydrogen gas in a displacement reaction . The zinc ions are soluble in the acid . </P> <P> The solubility of a substance is an entirely different property from the rate of solution, which is how fast it dissolves . The smaller a particle is, the faster it dissolves although there are many factors to add to this generalization . </P> <P> Crucially solubility applies to all areas of chemistry, geochemistry, inorganic, physical, organic and biochemistry . In all cases it will depend on the physical conditions (temperature, pressure and concentration) and the enthalpy and entropy directly relating to the solvents and solutes concerned . By far the most common solvent in chemistry is water which is a solvent for most ionic compounds as well as a wide range of organic substances . This is a crucial factor in acidity / alkalinity and much environmental and geochemical work . </P>

What word is used to describe the solubility of two liquids in each other