vapor pressure
DESCRIPTION
Pressure exerted by a vapor in equilibrium with its liquid or solid phase. Vapor Pressure. Vapor Pressure. At any temperature, some molecules in a liquid have enough energy to escape. As the temperature rises, the fraction of molecules that have enough energy to escape increases. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/1.jpg)
Vapor Pressure• Pressure exerted by a vapor in equilibrium with
its liquid or solid phase
![Page 2: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/2.jpg)
Vapor Pressure• At any temperature, some molecules in a
liquid have enough energy to escape.• As the temperature rises, the fraction of
molecules that have enough energy to escape increases.
![Page 3: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/3.jpg)
Vapor Pressure
As more molecules escape the liquid, the pressure they exert increases.
![Page 4: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/4.jpg)
Vapor Pressure
The liquid and vapor reach a state of dynamic equilibrium: liquid molecules evaporate and vapor molecules condense at the same rate.
![Page 5: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/5.jpg)
Gas-Liquid Equilibration
![Page 6: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/6.jpg)
Liquid Evaporates when no Equilibrium is Established
![Page 7: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/7.jpg)
Vapor Pressure• The boiling point of a
liquid is the temperature at which its vapor pressure equals atmospheric pressure.
• The normal boiling point is the temperature at which its vapor pressure is 760 torr.
![Page 8: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/8.jpg)
![Page 9: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/9.jpg)
Vapor Pressure and Boiling PointVapor Pressure and Boiling Point•Liquids boil when the external pressure equals the vapor pressure.•Temperature of boiling point increases as pressure increases.•Two ways to get a liquid to boil: increase temperature or decrease pressure.–Pressure cookers operate at high pressure. At high pressure the boiling point of water is higher than at 1 atm. Therefore, there is a higher temperature at which the food is cooked, reducing the cooking time required.
•Normal boiling point is the boiling point at 760 mmHg (1 atm).
![Page 10: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/10.jpg)
Phase DiagramsPhase Diagrams• Any temperature and pressure combination not
on a curve represents a single phase.
![Page 11: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/11.jpg)
![Page 12: Vapor Pressure](https://reader035.vdocuments.net/reader035/viewer/2022062410/5681602f550346895dcf442b/html5/thumbnails/12.jpg)
Clausius-Clapeyron Equation