The vapour pressure is the equilibrium pressure from a liquid or a solid at a specific temperature. The equilibrium vapour pressure of a liquid or solid is not affected by the amount of contact with the liquid or solid interface.
The normal boiling point of a liquid is the temperature at which the vapour pressure is equal to one atmosphere (unit).
For two-phase systems (e.g., two liquid phases), the vapour pressure of the system is the sum of the vapour pressures of the two liquids. In the absence of stronger inter-species attractions between like-like or like-unlike molecules, the vapour pressure follows Raoult's Law, which states that the partial pressure of each component is the product of the vapour pressure of the pure component and its mole fraction in the mixture. The total vapour pressure is the sum of the component partial pressures.
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Other articles related to "pressure, vapour pressure, vapour, vapour pressures":
... must be carefully evaluated for their outgassing and vapor pressure properties ... All materials, solid or liquid, have a small vapour pressure, and their outgassing becomes important when the vacuum pressure falls below this vapour pressure ... Then a sorption pump would be used to bring the pressure down to 10−4 Torr (10 mPa) ...
... The Kelvin equation describes the change in vapour pressure due to a curved liquid/vapor interface (meniscus) with radius (for example, in a capillary or over a droplet) ... The Kelvin equation may be written in the form where is the actual vapour pressure, is the saturated vapour pressure, is the surface tension, is the molar ... Equilibrium vapor pressure depends on droplet size ...
... is the process of forming aerosol mass from the condensation of a gaseous precursor, specifically a vapour ... In order for the vapour to condense, it must be supersaturated i.e ... its partial pressure must be greater than its vapour pressure ...
... All materials, solid or liquid, have a small vapour pressure, and their outgassing becomes important when the vacuum pressure falls below this vapour pressure ... Ultra-high vacuum systems are usually baked, preferably under vacuum, to temporarily raise the vapour pressure of all outgassing materials and boil them off ... off and evacuated, the system may be cooled to lower vapour pressures and minimize residual outgassing during actual operation ...
... Concentration Density Molarity pH Viscosity Specific heat Vapour pressure Boiling point Melting point kg HCl/kg kg HCl/m3 Baumé kg/L mol/dm3 mPa·s kJ/(kg·K) kPa °C °C 10% 104.80 6.6 1.048 2.87 −0 ... Vapour pressure values are taken from the International Critical Tables, and refer to the total vapour pressure of the solution ...
Famous quotes containing the words pressure and/or vapour:
“Destiny is an absolutely definite and inexorable ruler. Physical ability and moral determination count for nothing. It is impossible to perform the simplest act when the gods say no. I have no idea how they bring pressure to bear on such occasions; I only know that it is irresistible.”
—Aleister Crowley (18751947)
“Thy great leaves enfold
The ancient beards, the helms of ruby and gold
Of the crowned Magi; and the king whose eyes
Saw the Pierced Hands and Rood of elder rise
In Druid vapour and make the torches dim....”
—William Butler Yeats (18651939)