Vapour pressure definition

Vapour pressure means the pressure created when a substance evaporates. This is the pressure of the vapour of the substance, at any given temperature, in equilibrium with its liquid or solid form. The higher the vapour pressure, the more the substance tends to evaporate.
Vapour pressure means the equilibrium pressure of the saturated vapour above the liquid, expressed in Pascals (Pa) absolute at a specified temperature.
Vapour pressure means the pressure above the surface of a liquid relative to zero pressure (absolute). Also called true vapour pressure.

Examples of Vapour pressure in a sentence

  • ASTM D445 or D446 -receipt temperature -reference temperature Vapour pressure not to exceed 103kPa. ASTM D323 ▇▇▇▇ Vapour Pressure Receipt temperature not to exceed 38.0 C.


More Definitions of Vapour pressure

Vapour pressure means the dry vapour pressure equivalent as determined using the American Society for Testing and Materials (ASTM International) Standard D5191 “Standard Test Method for Vapour Pressure of Petroleum Products (Mini Method)”.
Vapour pressure means the pressure exerted by the gaseous form of a substance in equilibrium with its liquid or solid form;
Vapour pressure of petrol means the volatility of the petrol at 37.8 degrees Celsius measured:
Vapour pressure means vapour pressure at 38 degrees Celsius as determined by the Reid method;
Vapour pressure means the petrol's volatility at 37·8oC measured using ASTM D4953 Standard Test Method for Vapour Pressure of Gasoline and Gasoline-Oxygenate Blends (Dry Method) published by the American Society for Testing and Materials as in force from time to time.
Vapour pressure means the absolute pressure of a liquid exerted by the gas produced by evaporation from the liquid when gas and liquid are in equilibrium at the prevailing temperature and the gas or liquid ratio is effectively zero.

Related to Vapour pressure

  • Reid vapor pressure means the vapor pressure of crude oil or other volatile petroleum products at 100 degrees Fahrenheit as determined by the latest edition of ASTM D6377 (RVPE): Standard Test Method for Determination of Vapor Pressure of Crude Oil.

  • True vapor pressure means the equilibrium partial pressure exerted by a petroleum liquid as determined in accordance with methods described in American Petroleum Institute (API) Bulletin 2517, Evaporation Loss from External Floating Roof Tanks, 1980. The API procedure may not be applicable to some high viscosity or high pour crudes. Available estimates of true vapor pressure may be used in special cases such as these.

  • Pressure means the total load or force per unit area acting on a surface.

  • Low water pressure means water pressure below the regulatory reference level which is the minimum pressure when demand on the system is not abnormal.

  • Operating pressure means the pressure at which the parts of an irrigation system are designed by the manufacturer to operate.