A mixture is the aggregation of several substances or bodies that do not chemically combine with each other. Each of the substances that make up a mixture is called component e, which when being together or separated retain their characteristic properties, and intervene in variable proportions.
Many of the substances that we handle on a daily basis are mixtures, they have numerous uses in daily life and in industry. Examples of them are: concrete, earth, wood, paper, granite, air, oil, milk, soup, and many other foods and objects.
The mixtures can be homogeneous and heterogeneous, in the former the components cannot be distinguished, because they are uniformly distributed throughout the mixture; that is, the composition is the same throughout. This type of mixture is known as a solution; for example, when a tablespoon of sugar is dissolved in water.
In the latter, the components are easily distinguished, and each of them can be visibly appreciated; that is, the composition of the mixture is not uniform. For example, water and oil, salads, iron shavings in the sand, etc.
Homogeneous mixtures are true solutions since experimentally their two components have the properties of a single phase. In contrast, heterogeneous mixtures undergo two phases with their components, and can be colloidal or colloid solutions, and suspensions.
Regardless of the type of mixture, heterogeneous or homogeneous, it can be in solid, liquid or gaseous state, and it can be formed and re-separated from its components using mechanical procedures such as sedimentation, decantation, filtration, magnetization, centrifugation, sieving and levigation; and physical procedures such as evaporation, distillation, crystallization, chromatography, freezing, and liquefaction.
Thus, the sugar can be separated from the aqueous solution by heating and evaporating the solution until dry. And to separate the components of the iron and sand mixture, a magnet can be used to recover the iron shavings, since the magnet does not attract the sand. After separation, no change will have occurred in the properties of the components of the mixture.
It should be noted that the term mixture is also referred to the union, link or grouping of things or elements; in some cases, different from each other, such as, for example, a mixture of races, a mixture of colors, a mixture of music or sound, a mixture of flavors, among others.
