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A list of all chemical substances constituting a mixture is called Mixture composition.
The chemical properties of mixtures may differ from those of any constituent components.
Unlike pure substances the mixtures in a state of Thermodynamic equilibrium may see various phases occupy a continuous area in PT Diagram (see for example Vapour Liquid Equilibrium).
Mixtures with two components are called Binary Mixtures and apart from a wide practical value they have a zoomed value in academic studies which allow to help understand and model behaviour of all mixtures.
A mixture in a fluid state (liquid, gas or supercritical fluid) is called a fluid mixture.
In petroleum industry the most popular mixtures are hydrocarbons and water (H2O).
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