sloka4444
Mar 6, 2009, 10:58 AM
At triple point of water all the three phases of water i.e. solid liquid and gaseous phases of water is said to have same vapor pressure.V.P means pressure exerted by the gas molecules of a particular liquid on the surface of the that liquid when the liquid is in equilibrium with the gas molecules.Then it is termed as v.p of that particular liquid. But how can solids and gases can have vapor pressure?? Only liquids have V.P.
Perito
Mar 6, 2009, 11:13 AM
Only liquids have V.P.
That is quite incorrect.
If you'll notice in the winter snow sublimes. You can notice snow disappearing in areas where the sun hits it and where there are shadows. When I was a young boy, my mother would hang sheets out on the line. They would freeze. After a couple of hours, she would bring them in and they would be dry.
Dry Ice (solid CO2) is another substance that sublimes easily.
For many solids, the vapor pressure is very low -- so low that you never see anything evaporate. But it's still not zero. Those solids that sublime easily have high vapor pressures.
The vapor pressure of a gas is simply its partial pressure.