fugacity

fu·ga·cious   (fyōō-gā'shəs)    adj.   Passing away quickly; evanescent. Botany Withering or dropping off early. [From Latin fugāx, fugāc-, from fugere, to flee.] fu·ga'cious·ly adv., fu·ga'cious·ness, fu·gac'i·ty (-gās'ĭ-tē) n.

Main Entry: fu·gac·i·ty
Pronunciation: fyü-'gas-&t-E
Function: noun
Inflected Form: plural -ties
: thevapor pressure of a vapor assumed to be an ideal gas obtained by correcting the determined vapor pressure and useful as a measure of the escaping tendency of a substance from a heterogeneous system

fugacity fu·gac·i·ty (fy&oomacr;-gās'ĭ-tē)
n.
A measure of the tendency of a substance, often a fluid, to move from one phase to another or from one site to another.

fugacity

a measure of the tendency of a component of a liquid mixture to escape, or vaporize, from the mixture. The composition of the vapour form of the mixture, above the liquid, is not the same as that of the liquid mixture; it is richer in the molecules of that component that has a greater tendency to escape from the liquid phase. The fugacity of a component in a mixture is essentially the pressure that it exerts in the vapour phase when in equilibrium with the liquid mixture.

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