tension de vapeur
- Domaine
-
- chimieanalyse thermique
- Date
Définition :
Pression à une température donnée à laquelle la phase solide (ou liquide) est en équilibre thermodynamique avec la phase vapeur.
Terme :
- tension de vapeur n. f.
Terme associé :
- pression de vapeur n. f.
Traductions
-
anglais
Date :Définition
A value characteristic of all liquids and some solids. It is the pressure exerted by the vapor when evaporation and condensation exactly balance each other in a closed system, that is, when as many molecules are entering the liquid as are leaving it. This is called the equilibrium state between a liquid and its vapor. It is a function of the substance and of its temperature. This pressure rise with temperature because of the increase in molecular kinetics caused by the added energy. When the pressure of the vapor reaches that of the atmosphere, the liquid boils.
Note :
Some alcohols and most hydrocarbon liquids have lower vapor pressure than water. It is usually expressed in millimeters or mercury (mm Hg); 760 mm Hg equals 14.7 psi, or 1 atmosphere.
Termes :
- vapor pressure États-Unis
- vapour pressure Royaume-Uni
Terme associé :
- vapour tension