Realgemische

Realgemische is a German-language term that can be translated as real mixtures or real-world mixtures. In general usage, it refers to systems composed of two or more substances that are physically blended, where each component retains its own properties and the overall composition can vary. This distinguishes real mixtures from pure substances and from compounds with fixed chemical formulas.

In chemistry, realgemische are characterized by the physical combination of components whose proportions can change and which may exist in one or more phases. They are classified as homogeneous real mixtures (solutions or solid solutions, where components are distributed uniformly) or heterogeneous real mixtures (where different phases or particles are distinguishable, such as sand in water or a granite sample). The constituents retain identity, and properties such as boiling point, density, and refractive index depend on composition and conditions like temperature and pressure. Separation methods such as distillation, filtration, chromatography, and centrifugation are used to deconvolute realgemische into their components.

The term is sometimes used in education and applied science to emphasize real-world complexity beyond idealized models (for example, ideal solutions or ideal gases). Realgemische may exhibit non-ideal behavior due to interactions between components, leading to deviations from simple quantitative rules.

Examples commonly cited in teaching and practice include air (a mixture of nitrogen, oxygen, argon, CO2, and others) and seawater (water with dissolved salts and organic matter). See also Gemisch, Lösung, Suspension, Kolloid, Homogenes Gemisch, Heterogenes Gemisch.