Vapour Pressure
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.
Read more about this topic: Vapor
Famous quotes containing the words vapour and/or pressure:
“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 (1865–1939)
“The mother whose self-image is dependent on her children places on those children the responsibility for her own identity, and her involvement in the details of their lives can put great pressure on the children. A child suffers when everything he or she does is extremely important to a parent; this kind of over-involvement can turn even a small problem into a crisis.”
—Grace Baruch (20th century)