]> An alloy is a partial or complete solid solution of one or more elements in a metallic matrix. Complete solid solution alloys give single solid phase microstructure, while partial solutions give two or more phases that may be homogeneous in distribution depending on thermal (heat treatment) history. Alloys usually have different properties from those of the component elements. [Wikipedia] Chemical substance, in chemistry, are material objects that can undergo various transformations related to artificial or natural phenomena [Wikipedia] In chemistry, a mixture is when two or more different substances are mixed together but not combined chemically. The molecules of two or more different substances are mixed in the form of solutions, suspensions, and colloids. [Wikipedia] The substance present in a solution in the smaller amount. For convenience, water is generally considered the solvent even in concentrated solutions with water molecules in the minority. In chemistry, a solution is a homogeneous mixture composed of two or more substances. In such a mixture, a solute is dissolved in another substance, known as a solvent. All solutions are characterized by interactions between the solvent phase and solute molecules or ions that result in a net decrease in free energy. [Wikipedia] The total amount of solute species that will remain indefinitely in a solution maintained at constant temperature and pressure in contact with the solid crystals from which the solutes were derived. Volatility is a measure of the tendency of a liquid (or solid) to evaporate into a gaseous form. Higher volatility indicates a higher tendency to evaporate and a lower volatility means that it has a lower tendency to evaporate. A simulation approach to studying the chemical evolution of a (natural) system.