Intensive and extensive properties: Difference between revisions

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By contrast, an '''extensive property''' is one that is additive for independent, noninteracting subsystems.<ref name=IUPAC>[http://media.iupac.org/publications/books/gbook/IUPAC-GB3-2ndPrinting-Online-22apr2011.pdf IUPAC Green Book] Quantities, Units and Symbols in Physical Chemistry (3rd edn. 2007), page 6 (page 20 of 250 in PDF file)</ref> The property is proportional to the amount of material in the system. For example, both the mass and the volume of a diamond are directly proportional to the amount that is left after cutting it from the raw mineral. Mass and volume are extensive properties, but hardness is intensive.

The ratio of two extensive properties is scale-invariant, and is therefore an intensive property. For example, when gravity may be assumed constant, the ratio of the extensive properties mass and volume, the density, is an intensive property.

This terminology of intensive and extensive properties was introduced by [[Richard C. Tolman]] in 1917.<ref name=Redlich/>