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Mixture

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A suspension of flour in water, a heterogeneous mixture

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.

While there are no physical changes in a mixture, the physical properties of a mixture, such as its melting point, may differ from those of its components. Mixtures can usually be separated into its original components by mechanical means. Mixtures are either homogeneous or heterogeneous.

Mixtures are the product of a blending or mixing of chemical substances like elements and compounds, without chemical bonding or other chemical change, so that each ingredient substance retains its own chemical properties and makeup.[1]

Suspensions

A heterogeneous mixture is one with uneven distribution within the mixture (due to phases or particle size). A suspension is when the particles of one substance are suspended in the other substance (the two substances do not mix into a 'seam-less' mixture- a 'whole'). An example of a suspension is putting flour in water. You can see the water as a separate substance from the particles of flour (the flour is obviously not blended with the water). A Mixture can be reversed unlike a chemical reaction.

Colloidal dispersions

Colloids are mixtures in which the particles of one or more components have at least one dimension in the range of 1 to 1000 nm, larger than those in a solution but smaller than those in a suspension. Colloids are the same as suspensions, except they don’t leave sediments.[2] In general, a colloid or colloidal dispersion is a substance with components of one or two phases. It creates the Tyndall effect when light passes through it. A colloid will not settle. Jelly, milk, blood, paint, fog, shampoo, and glue are examples of colloid dispersions.

mixture's can be from copper to h2o if you put these together you get copper02

Mixtures and compounds

A compound is not a mixture. A compound has very different properties than the elements it is made of, but a mixture contains several substances which keep their properties.

References

  1. ^ Atkins' Physical Chemistry, 7th Ed. by Julio De Paula, P.W. Atkins ISBN 0198792859
  2. ^ Chemistry: Matter and its Changes, 4th Ed. by Brady, Senese, ISBN 0471215171

IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "mixture". doi:10.1351/goldbook.M03949